Uplink transmit power allocation and power headroom reporting by a user equipment in a multi-connectivity environment

ABSTRACT

Techniques for wireless communication are described, which may include establishing a connection, by a user equipment (UE), with a first and second evolved NodeB (eNB), wherein each of the eNBs provide radio resources to the UE for respective uplink communications; receiving from the first eNB, at the UE, an indication including an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmitting the uplink communications from the UE to the first and second eNBs based on the indication. The techniques may further include coordinating, by a first eNB, multi-connectivity communication for a UE with at least the first eNB and a second eNB; determining for the UE, at the eNB, an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmitting an indication including the allocation of uplink transmit power allocation from the first eNB to the UE.

CROSS REFERENCES

The present application for patent claims priority to U.S. ProvisionalPatent Application No. 61/933,829 by Vajapeyam et al., entitled “UplinkTransmit Power Allocation And Power Headroom Reporting By A UserEquipment In A Multi-Connectivity Environment,” filed Jan. 30, 2014,assigned to the assignee hereof, and expressly incorporated by referenceherein.

BACKGROUND

1. Field of the Disclosure

The following relates generally to wireless communication, and morespecifically to selecting coverage enhancement techniques.

2. Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

Generally, a wireless multiple-access communications system may includea number of evolved NodeBs (eNBs), each simultaneously supportingcommunication for multiple user equipments (UEs). An eNB may communicatewith a UE on both downstream communication links (in which data orcontrol signals are transmitted from the eNB to the UE) and upstreamcommunication links (in which data or control signals are transmittedfrom the UE to the eNB).

In a multi-connectivity environment (e.g., multiflow), a UE may connectsimultaneously to two or more eNBs. Additionally, the UE may beconstrained by a maximum transmit power. The eNBs may attempt toseparately control an uplink transmit power of the UE, which may attimes result in a request for the UE to exceed the maximum transmitpower in place.

SUMMARY

The described methods, systems, and devices generally enable a UE in amulti-connectivity environment to allocate uplink transmit power betweena first eNB and a second eNB, or enable a UE to report power headroom toa first eNB or a second eNB, or enable a UE to modify an allocation ofuplink transmit power between a first eNB and a second eNB (e.g., borrowpower from an eNB or cell and allocate the power to another eNB orcell).

According to a first aspect of the disclosure, a method of wirelesscommunication by a user equipment (UE) is described. In oneconfiguration, the method may include establishing a connection with afirst evolved NodeB (eNB) and a second eNB, wherein each of the firsteNB and the second eNB provide radio resources to the UE for respectiveuplink communications; receiving from the first eNB, at the UE, anindication including an allocation of uplink transmit power between thefirst eNB and at least the second eNB; and transmitting the uplinkcommunications from the UE to the first eNB and the second eNB based onthe indication.

According to another aspect of the disclosure, a device for wirelesscommunication by a UE is described. In one configuration, the device mayinclude means for establishing a connection with a first evolved NodeB(eNB) and a second eNB, wherein each of the first eNB and the second eNBprovide radio resources to the UE for respective uplink communications;means for receiving from the first eNB, at the UE, an indicationcomprising an allocation of uplink transmit power between the first eNBand at least the second eNB; and means for transmitting the uplinkcommunications from the UE to the first eNB and the second eNB based onthe indication.

According to another aspect of the disclosure, a device for wirelesscommunication by a UE may include a processor and a memory in electroniccommunication with the processor. Instructions may be stored in thememory, the instructions being executable by the processor to establisha connection with a first evolved NodeB (eNB) and a second eNB, whereineach of the first eNB and the second eNB provide radio resources to theUE for respective uplink communications; receive from the first eNB, atthe UE, an indication comprising an allocation of uplink transmit powerbetween the first eNB and at least the second eNB; and transmit theuplink communications from the UE to the first eNB and the second eNBbased on the indication.

According to another aspect of the disclosure, a non-transitorycomputer-readable medium storing code for wireless communication by a UEis described. The code may include instructions executable to: establisha connection with a first evolved NodeB (eNB) and a second eNB, whereineach of the first eNB and the second eNB provide radio resources to theUE for respective uplink communications; receive from the first eNB, atthe UE, an indication comprising an allocation of uplink transmit powerbetween the first eNB and at least the second eNB; and transmit theuplink communications from the UE to the first eNB and the second eNBbased on the indication.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the indication may be based atleast in part on an uplink/downlink (UL/DL) configuration of the firsteNB or the second eNB when the first eNB or the second eNB operates in atime division duplex (TDD) mode. The indication may, for example,include a time index.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the indication may include anindication of subframes on which substantially all uplink transmit poweris allocated to the first eNB or to the second eNB. Additionally oralternatively, the indication comprises an allocation of total uplinktransmit power between communications with the first eNB and the secondeNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for generating a power headroom reportat the UE, the power headroom report including power headroominformation for both the first eNB and the second eNB, and processes,features, means, or instructions for transmitting the power headroomreport to the first eNB. The power headroom information may be based atleast in part on scheduling information from both the first eNB and thesecond eNB; and the first eNB and the second eNB may schedulecommunications with the UE on different sets of resources.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, a second indication comprisingan allocation of uplink transmit power may be received from the firsteNB in response to the power headroom report, wherein the secondindication changes the allocation of uplink transmit power allocated tothe first eNB or the second eNB. Power headroom may be determined forthe first eNB and the second eNB with respect to the uplink transmitpower allocated to the first eNB or the second eNB after receiving thesecond indication.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the power headroomreport to the first eNB or the second eNB in response to a triggeringmessage received from the first eNB or the second eNB. The triggeringmessage may include an indication that the first eNB or the second eNBhas activated an uplink cell.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the power headroomreport to the second eNB. Transmitting the power headroom report to thesecond eNB may be based on a determination that uplink resources areallocated to the UE for an uplink transmission to the second eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, triggering the power headroomreport at the UE may be based on a determination that an allocation ofuplink transmit power of the UE for the first eNB or the second eNB hascrossed a threshold. The threshold may include a maximum uplink transmitpower for the first eNB or the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for triggering the power headroomreport at the UE based on a measured pathloss of the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may include processes,features, means, or instructions for generating a power headroom reportat the UE, the power headroom report including power headroominformation for the second eNB. The methods, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the power headroomreport to the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for modifying, by the UE, theallocation of uplink transmit power between the first eNB and the secondeNB. The modification of the allocation of uplink transmit power may bebased on a priority of uplink data or control information for one of theeNBs with respect to the other of the eNBs. A power headroom report maybe triggered at the UE based on the modification by the UE of theallocation of uplink transmit power between the first eNB and the secondeNB. The power headroom report may include an indication that an uplinktransmit power for one of the first eNB or the second eNB has exceeded amaximum transmit power allocated to that eNB. A second indication may bereceived from the first eNB, the second indication including anallocation of uplink transmit power between the first eNB and the secondeNB. The second indication may be in response to the modification, bythe UE, of the allocation of uplink transmit power between the first eNBand the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining an allocation of uplinktransmit power between a plurality of cells controlled by the first eNBor the second eNB based on the indication.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining, at the UE, an uplinktransmit power for each of a plurality of cells controlled by the firsteNB or the second eNB based on the indication.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the first eNB may be a mastereNB and the second eNB may be a secondary eNB.

According to another aspect of the disclosure, a method of wirelesscommunication is described. In one configuration, the method may includecoordinating, by a first eNB, multi-connectivity communication for a UEwith at least the first eNB and a second eNB; determining for the UE, atthe eNB, an allocation of uplink transmit power between the first eNBand at least the second eNB; and transmitting an indication includingthe allocation of uplink transmit power allocation from the first eNB tothe UE.

According to another aspect of the disclosure, a device for wirelesscommunication, may include means for coordinating, by a first evolvedNodeB (eNB), multi-connectivity communication for a user equipment (UE)with at least the first eNB and a second eNB; means for determining forthe UE, at the eNB, an allocation of uplink transmit power between thefirst eNB and at least the second eNB; and means for transmitting anindication comprising the allocation of uplink transmit power allocationfrom the first eNB to the UE.

According to another aspect of the disclosure, a device for wirelesscommunication may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to: coordinate, by afirst evolved NodeB (eNB), multi-connectivity communication for a userequipment (UE) with at least the first eNB and a second eNB; determinefor the UE, at the eNB, an allocation of uplink transmit power betweenthe first eNB and at least the second eNB; and transmit an indicationcomprising the allocation of uplink transmit power allocation from thefirst eNB to the UE.

According to another aspect of the disclosure, a non-transitorycomputer-readable medium storing code for wireless communication isdescribed. The code may include instructions executable to: coordinate,by a first evolved NodeB (eNB), multi-connectivity communication for auser equipment (UE) with at least the first eNB and a second eNB;determine for the UE, at the eNB, an allocation of uplink transmit powerbetween the first eNB and at least the second eNB; and transmit anindication comprising the allocation of uplink transmit power allocationfrom the first eNB to the UE.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, a power headroom report may bereceived from the UE, the power headroom report including power headroominformation for at least the first eNB and the second eNB. Theallocation of uplink transmit power between the first eNB and the secondeNB for the UE may be adjusted based on the power headroom report.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, an adjusted allocation ofuplink transmit power between the first eNB and the second eNB may bedetermined based on the power headroom report. The adjusted allocationof uplink transmit power may be transmitted to at least one of the UE orthe second eNB. The power headroom report may be received in response toat least one of: an uplink transmit power of the UE for the second eNB,a measured pathloss variation for the second eNB, or the second eNBactivating an uplink cell.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, a determination may be made,based on the power headroom report, that the UE has modified theallocation of uplink transmit power between the first eNB and the secondeNB. The adjusted allocation of uplink transmit power between the firsteNB and the second eNB for the UE may be based on the modification bythe UE to the allocation of uplink transmit power between the first eNBand the second eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the power headroom report maybe transmitted from the first eNB to the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for adjusting the allocation of uplinktransmit power between the first eNB and the second eNB based on amessage received at the first eNB from the second eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the allocation of uplinktransmit power between the first eNB and the second eNB may be based atleast in part on an uplink/downlink (UL/DL) configuration of the firsteNB or the second eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the indication may include atime index.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the allocation of uplinktransmit power between the first eNB and the second eNB may include anallocation of uplink transmit power between a plurality of cells of thefirst eNB or the second eNB.

Some examples of the method, devices, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the allocation ofuplink transmit power from the first eNB to the second eNB. Transmittingthe allocation of uplink transmit power from the first eNB to the secondeNB may include transmitting a message containing the allocation ofuplink transmit power over an X2 interface between the first eNB and thesecond eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, communications between the UEand the first eNB may be scheduled independently from communicationsbetween the UE and the second eNB.

In certain examples of the method, devices, or non-transitorycomputer-readable medium described above, the first eNB may be a mastereNB and the second eNB may be a secondary eNB.

Further scope of the applicability of the described methods andapparatuses will become apparent from the following detaileddescription, claims, and drawings. The detailed description and specificexamples are given by way of illustration only, since various changesand modifications within the spirit and scope of the description willbecome apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 shows a block diagram of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2 shows a block diagram of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 3 shows a message flow between a UE, a first eNB, and at least asecond eNB, in accordance with various aspects of the presentdisclosure;

FIG. 4 shows a message flow between a UE, a first eNB, and at least asecond eNB, in accordance with various aspects of the presentdisclosure;

FIG. 5 shows a message flow between a UE, a first eNB, and at least asecond eNB, in accordance with various aspects of the presentdisclosure;

FIG. 6 shows a block diagram of an example of a device usable forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 7 shows a block diagram of an example of a device usable forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 8 shows a block diagram of an example of a device usable forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 9 shows a block diagram of an example of a device usable forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 10 shows a block diagram of an example of a device usable forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 11 shows a block diagram of a UE configured for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 12 shows a block diagram illustrating an eNB configured forwireless communication, in accordance with various aspects of thepresent disclosure;

FIG. 13 is a flow chart illustrating a method of wireless communicationby a UE, in accordance with various aspects of the present disclosure;

FIG. 14 is a flow chart illustrating a method of wireless communicationby a UE, in accordance with various aspects of the present disclosure;

FIG. 15 is a flow chart illustrating a method of wireless communicationby a UE, in accordance with various aspects of the present disclosure;

FIG. 16 is a flow chart illustrating a method of wireless communication,in accordance with various aspects of the present disclosure; and

FIG. 17 is a flow chart illustrating a method of wireless communicationby a UE, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

In a multi-connectivity environment such as a multiflow environment, aUE may connect simultaneously to two or more eNBs. In such anenvironment, the UE may concurrently provide a physical uplink sharedchannel (PUSCH) or a physical uplink control channel (PUCCH) for eacheNB to which the UE connects. Additionally, the UE may be constrained bya maximum transmit power affecting all uplink communications inaggregate. Thus, as described herein, to prevent a UE from exceeding itsmaximum transmit power, the eNBs to which the UE connects may coordinatewith each other to determine an allocation of uplink transmit powerbetween the eNBs. To aid in this determination, power headroom reportsfrom the UE to one of the eNBs may include power headroom informationfor each of the eNBs to which the UE is currently connected.

A wireless communication system, such as a 3GPP “Long Term Evolution”(LTE) or “LTE-Advanced” (LTE-A) wireless communication system, mayprovide for various modes of communication between the UE and one ormore eNBs. Some of the modes of communication enable a UE tosimultaneously connect to multiple cells of one or more eNBs.

In a carrier aggregation mode of communication, a UE in an RRC_CONNECTEDstate may connect to multiple cells of a single eNB and consume radioresources provided by each of the cells. Because all of the cells aremanaged by a single eNB, communications between the UE and the multiplecells may be scheduled by the single eNB and there may be tightcoordination amongst the cells.

In a coordinated multi-point (CoMP) mode of communication, a UE in anRRC_CONNECTED state may consume radio resources provided by more thanone eNB. Despite the cells being managed by more than one eNB, there maybe tight coordination amongst the cells. The tight coordination may beprovided, for example, as a result of communications being made over thesame carrier or as a result of an ideal backhaul between the multipleeNBs. The ideal backhaul may enable a fast transmission of feedbackbetween the multiple eNBs. Also, communications between the UE and themultiple eNBs may be scheduled by a single eNB.

In a multi-connectivity mode of communication, a UE in an RRC_CONNECTEDstate may connect to multiple cells managed by more than one eNB andconsume radio resources provided by each of the eNBs. Examples ofmulti-connectivity include, but are not limited to, multiflow anddual-connectivity. However, because communications with different eNBsmay be made over different carriers and be independently scheduled bydifferent eNBs, and because there may exist a non-ideal backhaul thatprovides slower transmission of feedback between eNBs, only loosecoordination may exist amongst the cells of different eNBs.

The techniques described herein are not limited to LTE/LTE-A wirelesscommunication systems, and may also be used for various wirelesscommunication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Aare commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA system may implement a radiotechnology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). LTE and LTE-Advanced (LTE-A) are new releases of UMTS that useE-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described indocuments from an organization named “3rd Generation PartnershipProject” (3GPP). CDMA2000 and UMB are described in documents from anorganization named “3rd Generation Partnership Project 2” (3GPP2). Thetechniques described herein may be used for the systems and radiotechnologies mentioned above as well as other systems and radiotechnologies. The description below, however, describes an LTE/LTE-Awireless communication system for purposes of example, and LTE/LTE-Aterminology is used in much of the description below, although thetechniques are applicable beyond LTE/LTE-A applications.

The following description provides examples, and is not limiting of thescope, applicability, or configuration set forth in the claims. Changesmay be made in the function and arrangement of elements discussedwithout departing from the spirit and scope of the disclosure. Variousembodiments may omit, substitute, or add various procedures orcomponents as appropriate. For instance, the methods described may beperformed in an order different from that described, and various stepsmay be added, omitted, or combined. Also, features described withrespect to certain embodiments may be combined in other embodiments.

FIG. 1 shows a block diagram of a wireless communication system 100, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 100 may include a plurality of evolved NodeBs(eNBs) 105 and eNBs 135, a number of user equipments (UEs) 115, and acore network 130. Some of the eNBs 105 or 135 may communicate controlinformation or user data with the core network 130 through backhaul 132.In some embodiments, some of the eNBs 105 or 135 may communicate, eitherdirectly or indirectly, with each other over backhaul links 134, whichmay be wired or wireless communication links. The wireless communicationsystem 100 may support operation on multiple carriers (waveform signalsof different frequencies). Multi-carrier transmitters may transmitmodulated signals simultaneously on the multiple carriers. For example,each communication link 125 may be a multi-carrier signal modulatedaccording to various radio technologies. Each modulated signal may besent on a different carrier and may carry control information (e.g.,reference signals, control channels, etc.), overhead information, data,etc.

The eNBs 105 or 135 may wirelessly communicate with the UEs 115 via oneor more eNB antennas. Each of the eNBs 105 or 135 may providecommunication coverage for a respective coverage area 110. In someembodiments, an eNB 105 or 135 may be referred to as, or include, a basestation, a base transceiver station (BTS), a radio base station, a radiotransceiver, a basic service set (BSS), an extended service set (ESS),an evolved NodeB (eNB), a Home eNodeB, or some other suitableterminology. The coverage area 110 for an eNB 105 or 135 may be dividedinto sectors making up only a portion of the coverage area (not shown).The wireless communication system 100 may include eNBs 105 or 135 ofdifferent types (e.g., macro, micro, or pico eNBs). The eNBs 105 or 135may be associated with the same or different access networks or mobilenetwork operator (MNO) deployments. The coverage areas of different eNBs105 or 135, including the coverage areas of the same or different typesof eNBs, belonging to the same or different MNOs or access networks, mayoverlap.

In some embodiments, the wireless communication system 100 may includean LTE/LTE-A wireless communication system (or network). The wirelesscommunication system 100 may be a Heterogeneous LTE/LTE-A/LTE-U networkin which different types of eNBs provide coverage for variousgeographical regions. For example, each eNB 105 or 135 may providecommunication coverage for a macro cell, a pico cell, a femto cell, orother types of cell. Small cells such as pico cells, femto cells, orother types of cells may include low power nodes or LPNs. A macro cellwould generally cover a relatively large geographic area (e.g., severalkilometers in radius) and may allow unrestricted access by UEs withservice subscriptions with the network provider. A pico cell wouldgenerally cover a relatively smaller geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell would also generally cover a relatively smallgeographic area (e.g., a home) and, in addition to unrestricted access,may also provide restricted access by UEs having an association with thefemto cell (e.g., UEs in a closed subscriber group (CSG), UEs for usersin the home, and the like). An eNB for a macro cell may be referred toas a macro eNB. An eNB for a pico cell may be referred to as a pico eNB.And, an eNB for a femto cell may be referred to as a femto eNB or a homeeNB. An eNB may support one or multiple (e.g., two, three, four, and thelike) cells.

The core network 130 may communicate with the eNBs 105 or 135 via abackhaul 132 or 134 (e.g., S1 application protocol, etc.). The eNBs 105or 135 may also communicate with one another, e.g., directly orindirectly via backhaul links 134 (e.g., via an X2 interface, etc.) orvia backhaul 132 (e.g., through core network 130). The wirelesscommunication system 100 may support synchronous or asynchronousoperation. For synchronous operation, the eNBs may have similar frame orgating timing, and transmissions from different eNBs may beapproximately aligned in time. For asynchronous operation, the eNBs mayhave different frame or gating timing, and transmissions from differenteNBs may not be aligned in time. The techniques described herein may beused for either synchronous or asynchronous operations.

The UEs 115 may be dispersed throughout the wireless communicationsystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso be referred to by those skilled in the art as a mobile device, amobile station, a subscriber station, a mobile unit, a subscriber unit,a wireless unit, a remote unit, a wireless device, a wirelesscommunication device, a remote device, a mobile subscriber station, anaccess terminal, a mobile terminal, a wireless terminal, a remoteterminal, a handset, a user agent, a mobile client, a client, or someother suitable terminology. A UE 115 may be a cellular phone, a personaldigital assistant (PDA), a wireless modem, a wireless communicationdevice, a handheld device, a tablet computer, a laptop computer, acordless phone, a wearable item such as a watch or glasses, a wirelesslocal loop (WLL) station, or the like. A UE 115 may be able tocommunicate with macro eNBs, pico eNBs, femto eNBs, relays, and thelike. A UE 115 may also be able to communicate over different accessnetworks, such as cellular or other WWAN access networks, or WLAN accessnetworks.

The communication links 125 shown in wireless communication system 100may include uplinks for carrying uplink (UL) transmissions (e.g., from aUE 115 to an eNB 105 or 135) or downlinks for carrying downlink (DL)transmissions (e.g., from an eNB 105 or 135 to a UE 115). The ULtransmissions may also be called reverse link transmissions, while theDL transmissions may also be called forward link transmissions. In somecases, the UL or DL transmissions may be made using MIMO communications(e.g., spatially multiplexed communications).

As noted above, a UE 115 may connect to multiple eNBs 105 at the sametime. In a multi-connectivity (e.g., multiflow) arrangement, each of theeNBs 105 to which the UE 115 connects may independently schedule uplinkand downlink transmissions between the UE 115 and that eNB 105. Toprevent the UE 115 from exceeding a maximum transmit power in place forthe UE 115, the eNBs 105 may communicate with each other to determine anallocation (e.g., a power allocation, a percentage allocation such as apercentage of uplink transmit power, etc.) of uplink transmit powerbetween the eNBs to which the UE 115 is currently connected. Thisallocation may be signaled to the UE 115 by one or more of the eNBs 105,and may change over time. By transmitting on the uplink in accordancewith the received allocation, the UE 115 may be prevented from exceedingthe maximum transmit power set by the eNBs 105.

FIG. 2 shows a block diagram of a wireless communication system 200, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 200 may include a UE 115-a, a first eNB 105-a, anda second eNB 135-a. The UE 115-a, first eNB 105-a, or second eNB 135-amay be respective examples of aspects of the UEs 115, eNBs 105, or eNBs135 described with reference to FIG. 1. In some embodiments, the firsteNB 105-a may include a master eNB (MeNB) and the second eNB 135-a mayinclude a secondary eNB (SeNB).

In one mode of operation, the first eNB 105-a may coordinatemulti-connectivity communication for the UE 115-a, in which the UE 115-amay communicate with one or more cells of the first eNB 105-a (e.g., amaster cell group (MCG) managed by the first eNB 105-a) over acommunication link (or links) 125-a, and with one or more cells of thesecond eNB 135-a (e.g., a secondary cell group (SCG) managed by thesecond eNB 135-a) over a communication link (or links) 125-b. The firsteNB 105-a and the second eNB 135-a may transmit feedback informationover a non-ideal backhaul link 134-a, such as a backhaul linkimplementing an X2 interface.

The first eNB 105-a and the second eNB 135-a may employ different mediaaccess control (MAC) entities with no coordination or very loosecoordination.

In the wireless communication system 200, a race condition may arise inwhich the total uplink transmit power requested of the UE 115-a by thefirst eNB 105-a and the second eNB 135-a exceeds the available uplinktransmit power of the UE 115-a. Such a race condition may adverselyaffect the UE's performance. Techniques to allocate the available uplinktransmit power of the UE between the first eNB 105-a and the second eNB135-a (or between more than two eNBs) may therefore be useful. Thetechniques may adapt power headroom reporting to a multi-connectivityenvironment.

Turning now to FIG. 3, there is shown a message flow 300 between a UE115-b, a first eNB 105-b, and at least a second eNB 135-b, in accordancewith various aspects of the present disclosure. Each of the UE 115-b,the first eNB 105-b, or the second eNB 135-b may be an example ofaspects of a respective one of the UEs 115, the first eNBs 105, or thesecond eNBs 135 described with reference to FIG. 1 or 2. In some cases,the first eNB 105-b may include a master eNB and the second eNB 135-bmay include a secondary eNB.

In the following description of the message flow 300, the messagesbetween the UE 115-b, the first eNB 105-b, or the second eNB 135-b maybe transmitted in a different order than the exemplary order shown, orthe operations performed by the UE 115-b, the first eNB 105-b, or thesecond eNB 135-b may be performed in different orders or at differenttimes. Certain messages or operations may also be left out of themessage flow 300, or other messages or operations may be added to themessage flow 300.

The message flow 300 may commence with the UE 115-b establishing aconnection 305 with the first eNB 105-b and a connection 315 with thesecond eNB 135-b. Each of the first eNB 105-b and the second eNB 135-bmay provide radio resources to the UE 115-b for respective uplinkcommunications. Each of the first eNB 105-b and the second eNB 135-b mayalso provide radio resources to the UE 115-b for respective downlinkcommunications. The first eNB 105-b may be used, at block 310, tocoordinate multi-connectivity communication for the UE 115-b with thefirst eNB 105-b and the second eNB 135-b. To assist the first eNB 105-bin coordinating multi-connectivity communication for the UE 115-b, thefirst eNB 105-b may transmit or receive backhaul communications 320 withthe second eNB 135-b. In some embodiments, the first eNB 105-b and thesecond eNB 135-b may communicate with the UE 115-b using differentcarriers, and thus, the backhaul communications 320 may be transmittedor received by means of a non-ideal backhaul link (e.g., a backhaul linkimplementing an X2 interface).

At block 325, the first eNB 105-b may determine an allocation (e.g., apower allocation, a percentage allocation such as a percentage of uplinktransmit power, etc.) of uplink transmit power between the first eNB105-b and at least the second eNB 135-b for the UE 115-b. The uplinktransmit power may in some cases be a maximum uplink transmit power.

Upon making the determination at block 325, the first eNB 105-b maytransmit an indication 330 of the allocation of uplink transmit powerbetween the first eNB 105-b and at least the second eNB 135-b to the UE115-b. In some cases, an indication 335 may also be transmitted to thesecond eNB 135-b. The indication(s) 330, 335 of the allocation of uplinktransmit power may in some cases include an indication of a maximumuplink transmit power, or a percentage of maximum uplink transmit power,allocated to each of the first eNB 105-b and at least the second eNB135-b.

In some examples, such as when the first eNB 105-b or the second eNB135-b operates in a TDD mode, the indication 330 of the allocation ofuplink transmit power between the first eNB 105-b and at least thesecond eNB 135-b may be based at least in part on an UL/DL configurationof the first eNB 105-b or the second eNB 135-b. For example, when an eNBoperates in a TDD mode, the number of active uplink carriers can changeover time based on the TDD configuration of each cell within the eNB.When the number of active uplink carriers used by an eNB is less duringa particular time period, more of the total uplink transmit poweravailable to the UE 115-b during the time period may be allocated toanother eNB with which the UE 115-b may communicate during the timeperiod. Conversely, more of the total uplink transmit power available tothe UE 115-b during the time period may be allocated to an eNB when thenumber of active uplink carriers used by the eNB is greater during aparticular time period.

In some examples, the indication 330 of the allocation of uplinktransmit power between the first eNB 105-b and at least the second eNB135-b may include an indication of subframes on which substantially alltransmit power may be allocated to the first eNB 105-b or to the secondeNB 135-b. For example, during a subframe or time period in which nouplink communications to an eNB are expected, substantially all uplinktransmit power may be allocated to one or more other eNBs.

In some cases, the indication 330 may include a time index. The timeindex may be used to indicate the subframes or time periods in which aneNB is allocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period. Thus, in certain examples, the indication 330may include a set of values parameterized by the time index.

At block 340, and in some variations, the UE 115-b may determine anallocation of uplink transmit power between a plurality of cells of thefirst eNB 105-b or the second eNB 135-b based on the indication 330 ofthe allocation of uplink transmit power between the first eNB 105-b andat least the second eNB 135-b. The allocation of uplink transmit powerbetween the plurality of cells may in some cases be semi-staticallyspecified in the indication 330 (e.g., the first eNB 105-b may specifyor configure an uplink transmit power value for each cell, which uplinktransmit power value may be used by the UE until the UE receives, fromthe first eNB 105-b, an adjusted indication of the allocation of uplinktransmit power between the first eNB 105-b and at least the second eNB135-b). The allocation of uplink transmit power between the plurality ofcells may in other cases be semi-statically specified per time index inthe indication (e.g., the first eNB 105-b may specify or configuremultiple uplink transmit power values for each cell, for each timeindex, which uplink transmit power values may be used by the UE 115-buntil the UE 115-b receives, from the first eNB 105-b, an adjustedindication including an allocation of uplink transmit power between thefirst eNB 105-b and at least the second eNB 135-b).

At block 340, the indication 330 of the allocation of uplink transmitpower between the first eNB 105-b and at least the second eNB 135-b mayinclude an allocation of total transmit power between communicationswith the first eNB 105-b and the second eNB 135-b. In these embodiments,the UE 115-b may determine, at the UE 115-b, an uplink transmit powerfor each of a plurality of cells controlled by the first eNB 105-b orthe second eNB 135-b based on the indication of the allocation of uplinktransmit power between the first eNB 105-b and at least the second eNB135-b. In some cases, the uplink transmit power per cell (e.g., themaximum uplink transmit power per cell) may be dynamically adjusted atthe UE 115-b.

At block 345, the first eNB 105-b may schedule communications, includinguplink communications, between the UE 115-b and the first eNB 105-b. Atblock 350, the second eNB 135-b may independently schedulecommunications, including uplink communications, between the UE 115-band the second eNB 135-b. Upon receiving the scheduling information 355or 360, the UE 115-b may transmit the uplink communications 365 to thefirst eNB 105-b and transmit the uplink communications 370 to the secondeNB 135-b based on the indication 330 of the allocation of uplinktransmit power between the first eNB 105-b and at least the second eNB135-b for the UE 115-b.

FIG. 4 shows a message flow 400 between a UE 115-c, a first eNB 105-c,and at least a second eNB 135-c, in accordance with various aspects ofthe present disclosure. Each of the UE 115-c, the first eNB 105-c, orthe second eNB 135-c may be an example of aspects of a respective one ofthe UEs 115, the first eNBs 105, or the second eNBs 135 described withreference to FIG. 1, 2, or 3. In some cases, the first eNB 105-c mayinclude a master eNB and the second eNB 135-c may include a secondaryeNB.

In the following description of the message flow 400, the messagesbetween the UE 115-c, the first eNB 105-c, or the second eNB 135-c maybe transmitted in a different order than the exemplary order shown, orthe operations performed by the UE 115-c, the first eNB 105-c, or thesecond eNB 135-c may be performed in different orders or at differenttimes. Certain messages or operations may also be left out of themessage flow 400, or other messages or operations may be added to themessage flow 400.

The message flow 400 may commence with the UE 115-c having established aconnection 405 with the first eNB 105-c and a connection 415 with thesecond eNB 135-c. Each of the first eNB 105-c and the second eNB 135-cmay provide radio resources to the UE 115-c for respective uplinkcommunications. Each of the first eNB 105-c and the second eNB 135-c mayalso provide radio resources to the UE 115-c for respective downlinkcommunications. The first eNB 105-c may be used, at block 410, tocoordinate multi-connectivity communication for the UE 115-c with thefirst eNB 105-c and the second eNB 135-c. To assist the first eNB 105-cin coordinating multi-connectivity communication for the UE 115-c, thefirst eNB 105-c may transmit or receive backhaul communications 420 withthe second eNB 135-c. In some embodiments, the first eNB 105-c and thesecond eNB 135-c may communicate with the UE 115-c using differentcarriers, and thus, the backhaul communications 420 may be transmittedor received by means of a non-ideal backhaul link (e.g., a backhaul linkimplementing an X2 interface).

When transmitting uplink communications to the first eNB 105-c and thesecond eNB 135-c, the UE 115-c may transmit the uplink communicationsbased on an indication of an allocation of uplink transmit power betweenthe first eNB 105-c and at least the second eNB 135-c for the UE 115-c.The indication may be provided to the UE 115-c by the first eNB 105-c.

At block 425, the first eNB 105-c may schedule communications, includinguplink communications, between the UE 115-c and the first eNB 105-c. Atblock 430, the second eNB 135-c may independently schedulecommunications, including uplink communications, between the UE 115-cand the second eNB 135-c. Upon receiving the scheduling information 435or 440, the UE 115-c may transmit uplink communications to the first eNB105-c or the second eNB 135-c based on the current indication of theallocation of uplink transmit power between the first eNB 105-c and atleast the second eNB 135-c for the UE 115-c.

At block 445, the UE 115-c may generate a power headroom report for aneNB (e.g., the first eNB 105-c or the second eNB 135-c). Generation of apower headroom report may be triggered for an eNB (e.g., the first eNB105-c or the second eNB 135-c) based on a condition of the eNB or aneighbor eNB (e.g., an eNB other than the eNB for which the powerheadroom report is triggered). By way of example, the condition of theeNB or the neighbor eNB may be a determination that an uplink transmitpower of the UE 115-c for the eNB or the neighbor eNB has crossed athreshold. In some cases, the threshold may include a maximum uplinkpower for the eNB. By way of further example, the condition of the eNBor the neighbor eNB may be a measured pathloss (e.g., a pathlossvariation satisfying a threshold) of the eNB or the neighbor eNB. By wayof still further example, the condition of the eNB or the neighbor eNBmay be a determination that the eNB or the neighbor eNB has activated anuplink cell.

A power headroom report may include power headroom information for boththe first eNB 105-c and the second eNB 135-c. Alternatively, the powerheadroom information may be for only the eNB 135 that triggered thepower headroom report. The inclusion of power headroom information forboth the first eNB 105-c and the second eNB 135-c may reduce powerheadroom report overhead and enable an eNB to estimate the total uplinktransmit power used by the UE 115-c. In some examples, the powerheadroom information may be computed per cell as:

PH(cell)=MaxPower(cell)−ActualTxPower(cell),  (Equation 1)

where PH(cell) is the power headroom of a cell, MaxPower(cell) is themaximum uplink transmit power of the cell, and ActualTxPower(cell) isthe current actual uplink transmit power of the cell.

In some cases, a power headroom report may be automatically transmittedto an eNB for which the power headroom report is triggered. In othercases, a power headroom report may be transmitted to an eNB for whichthe power headroom report is triggered in response to a triggeringmessage received from the eNB. In the latter cases, and by way ofexample, a power headroom report 455 triggered for the first eNB 105-cmay be transmitted to the first eNB 105-c in response to a triggeringmessage (e.g., a power headroom request 450) received from the first eNB105-c.

A power headroom report may be transmitted to the first eNB 105-c or thesecond eNB 135-c. In some cases, a power headroom report may betransmitted to the eNB for which the power headroom report was triggered(e.g., a power headroom report 455 triggered for the first eNB 105-c maybe transmitted to the first eNB 105-c, as indicated by the transmissionof power headroom report 455). In other cases, a power headroom reportmay be transmitted to the eNB for which the power headroom report wastriggered, as well as a neighbor eNB (e.g., a power headroom report 455triggered for the first eNB 105-c may be transmitted to the first eNB105-c and the second eNB 135-b, as indicated by the transmission ofpower headroom report 455 and power headroom report 455-a). In thelatter cases, the UE 115-c may in some cases transmit a power headroomreport to a neighbor eNB based on a determination that uplink resourcesare allocated to the UE 115-c for an uplink transmission to the neighboreNB. In some cases, an eNB for which a power headroom report istriggered may transmit (e.g., relay) a power headroom report to anothereNB, as indicated by the transmission of power headroom report 455-bfrom the second eNB 135-c to the first eNB 105-c. In additional oralternative examples, the first eNB 105-c and the second eNB 135-b mayexchange power headroom reports 135-b received from the UE 115-c overthe backhaul between the first eNB 105-c and the second eNB 135-c.

At block 460, the first eNB 105-c may adjust the allocation of uplinktransmit power between the first eNB 105-c and the second eNB 135-c forthe UE 115-c. The allocation may be adjusted based on the power headroomreport 455.

Upon making the adjustment at block 460, the first eNB 105-c maytransmit an indication 465 of the allocation of uplink transmit powerbetween the first eNB 105-c and at least the second eNB 135-c to the UE115-c. In some cases, an indication 470 may also be transmitted to thesecond eNB 135-c. The indication(s) 465, 470 of the allocation of uplinktransmit power may in some cases include an indication of a maximumuplink transmit power, or a percentage of uplink transmit power,allocated to each of the first eNB 105-c and at least the second eNB135-c.

When the first eNB 105-c or the second eNB 135-c operates in a TDD mode,the indication 465 of the allocation of uplink transmit power betweenthe first eNB 105-c and at least the second eNB 135-c may be based atleast in part on an UL/DL configuration of the first eNB 105-c or thesecond eNB 135-c. For example, when an eNB operates in a TDD mode, thenumber of active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

The indication 465 of the uplink transmit power between the first eNB105-c and at least the second eNB 135-c may include an indication ofsubframes on which substantially all transmit power may be allocated tothe first eNB 105-c or to the second eNB 135-c. For example, during asubframe or time period in which no uplink communications to an eNB areexpected, substantially all uplink transmit power may be allocated toone or more other eNBs.

In some cases, the indication 465 may include a time index. The timeindex may be used to indicate the subframes or time periods in which aneNB is allocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

At block 475, and after receiving the indication 465 of uplink transmitpower, the UE 115-c may determine power headroom for the first eNB 105-cand the second eNB 135-c with respect to the uplink transmit powerallocated to the first eNB 105-c or the second eNB 135-c in theindication 465 of uplink transmit power.

FIG. 5 shows a message flow 500 between a UE 115-d, a first eNB 105-d,and at least a second eNB 135-d, in accordance with various aspects ofthe present disclosure. Each of the UE 115-d, the first eNB 105-d, orthe second eNB 135-d may be an example of aspects of a respective one ofthe UEs 115, the first eNBs 105, or the second eNBs 135 described withreference to FIG. 1, 2, 3, or 4. In some cases, the first eNB 105-d mayinclude a master eNB and the second eNB 135-d may include a secondaryeNB.

In the following description of the message flow 500, the messagesbetween the UE 115-d, the first eNB 105-d, or the second eNB 135-d maybe transmitted in a different order than the exemplary order shown, orthe operations performed by the UE 115-d, the first eNB 105-d, or thesecond eNB 135-d may be performed in different orders or at differenttimes. Certain messages or operations may also be left out of themessage flow 500, or other messages or operations may be added to themessage flow 500.

The message flow 500 may commence with the UE 115-d having established aconnection 505 with the first eNB 105-d and a connection 515 with thesecond eNB 135-d. Each of the first eNB 105-d and the second eNB 135-dmay provide radio resources to the UE 115-d for respective uplinkcommunications. Each of the first eNB 105-d and the second eNB 135-d mayalso provide radio resources to the UE 115-d for respective downlinkcommunications. The first eNB 105-d may be used, at block 510, tocoordinate multi-connectivity communication for the UE 115-d with thefirst eNB 105-d and the second eNB 135-d. To assist the first eNB 105-din coordinating multi-connectivity communication for the UE 115-d, thefirst eNB 105-d may transmit or receive communications 520 with thesecond eNB 135-d. In some embodiments, the first eNB 105-d and thesecond eNB 135-d may communicate with the UE 115-d using differentcarriers, and thus, the communications 520 may be transmitted orreceived by means of a non-ideal backhaul link (e.g., a backhaul linkimplementing an X2 interface).

When transmitting uplink communications to the first eNB 105-d and thesecond eNB 135-d, the UE 115-d may transmit the uplink communicationsbased on an indication of an allocation of uplink transmit power betweenthe first eNB 105-d and at least the second eNB 135-d for the UE 115-d.The indication may be provided to the UE 115-d by the first eNB 105-d.

At block 525, the UE 115-d may modify the allocation of uplink transmitpower between the first eNB 105-d and the second eNB 135-d (or anallocation of uplink transmit power between cells). In some cases, theUE 115-d may modify the allocation of uplink transmit power by borrowinguplink transmit power allocated to one eNB or cell and re-allocating theborrowed uplink transmit power to another eNB or cell. The modificationof the allocation of uplink transmit power may in some cases be based ona priority of uplink data or control information for one of the eNBs(e.g., the first eNB 105-d or the second eNB 135-d) with respect to theother of the eNBs. The modification may also or alternately be based ona priority of uplink data or control information for a cell. Themodification may also or alternately be based on non-use of an uplink byan eNB or cell.

At block 530, the generation of a power headroom report may be triggeredbased on the modification of the allocation of uplink transmit powerbetween the first eNB 105-d and the second eNB 135-d (or between cellsof one or more of the first eNB 105-d and the second eNB 135-d). In somecases, the power headroom report may include an indication that anuplink transmit power for one of the first eNB 105-d or the second eNB135-d has exceeded a maximum transmit power allocated to that eNB.

The power headroom report may include power headroom information forboth the first eNB 105-d and the second eNB 135-d. The inclusion ofpower headroom information for both the first eNB 105-d and the secondeNB 135-d may reduce power headroom report overhead and enable an eNB toestimate the total uplink transmit power used by the UE 115-e. In someexamples, the power headroom information may be computed using Equation1.

The power headroom report 535 may be transmitted to the first eNB 105-dor the second eNB 135-d. In some cases, a power headroom report may betransmitted to an eNB that received power during modification of anallocation of uplink transmit power. Such a power headroom report mayinclude negative power headroom information. In other cases, a powerheadroom report may be transmitted to an eNB from which power wasborrowed during modification of an allocation of uplink transmit power.The latter power headroom report may subtract the borrowed power fromthe configured maximum power for an eNB or cell. In the case of powerheadroom information per cell, the power headroom information may becomputed as:

PH(cell)=MaxPower(cell)−ActualTxPower(cell)−BorrowedPower(cell),  (Equation2)

where BorrowedPower(cell) is the power borrowed from the cell.

At block 540, the first eNB 105-d may adjust the allocation of uplinktransmit power between the first eNB 105-d and the second eNB 135-d forthe UE 115-d. The allocation may be adjusted based on the power headroomreport 535.

Upon making the adjustment at block 540, the first eNB 105-d maytransmit an indication 545 of the allocation of uplink transmit powerbetween the first eNB 105-d and at least the second eNB 135-d to the UE115-d. In some cases, an indication 550 may also be transmitted to thesecond eNB 135-d. The indication(s) 545, 550 of the allocation of uplinktransmit power may in some cases include an indication of a maximumuplink transmit power allocated to each of the first eNB 105-d and atleast the second eNB 135-d.

In some embodiments, such as when the first eNB 105-d or the second eNB135-d operates in a TDD mode, the indication 545 of uplink transmitpower between the first eNB 105-d and at least the second eNB 135-d maybe based at least in part on an UL/DL configuration of the first eNB105-d or the second eNB 135-d. For example, when an eNB operates in aTDD mode, the number of active uplink carriers can change over timebased on the TDD configuration of each cell within the eNB. When thenumber of active uplink carriers used by an eNB is less during aparticular time period, more of the total uplink transmit poweravailable to the UE 115-d during the time period may be allocated toanother eNB with which the UE 115-d may communicate during the timeperiod. Conversely, more of the total uplink transmit power available tothe UE 115-d during the time period may be allocated to an eNB when thenumber of active uplink carriers used by the eNB is greater during aparticular time period.

In some embodiments, the indication 545 of the allocation of uplinktransmit power between the first eNB 105-d and at least the second eNB135-d may include an indication of subframes on which substantially alltransmit power may be allocated to the first eNB 105-d or to the secondeNB 135-d. For example, during a subframe or time period in which nouplink communications to an eNB are expected, substantially all uplinktransmit power may be allocated to one or more other eNBs.

In some cases, the indication 545 may include a time index. The timeindex may be used to indicate the subframes or time periods in which aneNB is allocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

At block 555, and after receiving the indication 545 of uplink transmitpower, the UE 115-d may determine power headroom for the first eNB 105-dand the second eNB 135-d with respect to the uplink transmit powerallocated to the first eNB 105-d or the second eNB 135-d in theindication 545 of uplink transmit power.

Referring now to FIG. 6, a block diagram 600 illustrates an example of adevice 605 usable for wireless communication, in accordance with variousaspects of the present disclosure. The device 605 may be an example ofone or more aspects of one of the UEs 115, first eNBs 105, or secondeNBs 135 described with reference to FIG. 1, 2, 3, 4, or 5. The device605 may also be a processor. The device 605 may include a receivermodule 610, a wireless communication management module 620, and atransmitter module 630. Each of these components may be in communicationwith each other.

The components of the device 605 may, individually or collectively, beimplemented with one or more application-specific integrated circuits(ASICs) adapted to perform some or all of the applicable functions inhardware. Alternatively, the functions may be performed by one or moreother processing units (or cores), on one or more integrated circuits.In other embodiments, other types of integrated circuits may be used(e.g., Structured/Platform ASICs, Field Programmable Gate Arrays(FPGAs), and other Semi-Custom ICs), which may be programmed in anymanner known in the art. The functions of each unit may also beimplemented, in whole or in part, with instructions embodied in amemory, formatted to be executed by one or more general orapplication-specific processors.

The receiver module 610 may include any number of receivers. In somecases the receiver module 610 may include a cellular receiver. Thecellular receiver may in some cases be an LTE/LTE-A receiver. Thecellular receiver may be used to receive various types of data orcontrol signals, collectively referred to as transmissions. Thetransmissions may be received over one or more communication channels ofa wireless communications system such as the wireless communicationsystem 100 or 200 described with reference to FIG. 1 or 2. In somecases, the receiver module 610 may include an alternate or additionaltype of receiver, such as an Ethernet or WLAN receiver. The Ethernet orWLAN receiver may also be used to receive various types of data orcontrol signals, and may also receive transmissions over one or morecommunication channels of a wireless communications system such as thewireless communication system 100 or 200.

The transmitter module 630 may include any number of transmitters. Insome cases the transmitter module 630 may include a cellulartransmitter. The cellular transmitter may in some cases be an LTE/LTE-Atransmitter. The cellular transmitter may be used to transmit varioustypes of data or control signals, collectively referred to astransmissions. The transmissions may be transmitted over one or morecommunication channels of a wireless communications system such as thewireless communication system 100 or 200. In some cases, the transmittermodule 630 may include an alternate or additional type of transmitter,such as an Ethernet or WLAN transmitter. The Ethernet or WLANtransmitter may also be used to transmit various types of data orcontrol signals, and may also transmit over one or more communicationchannels of a wireless communications system such as the wirelesscommunication system 100 or 200.

The wireless communication management module 620 may perform variousfunctions. In embodiments of the device 605 in which the device 605 maybe configured as a UE 115, the wireless communication management module620 may be used to manage multi-connectivity communication with a firsteNB 105 and at least one second eNB 135. The wireless communicationmanagement module 620 may also be used to manage an allocation of uplinktransmit power between the first eNB 105 and the at least one second eNB135.

In embodiments of the device 605 in which the device 605 may beconfigured as a first eNB 105, the wireless communication managementmodule 620 may be used to manage multi-connectivity communication for aUE 115 communicating with the device 605 and at least one second eNB135. The wireless communication management module 620 may also be usedto allocate uplink transmit power between the device 605 and the atleast one second eNB 135.

In embodiments of the device 605 in which the device 605 may beconfigured as a second eNB 135, the wireless communication managementmodule 620 may be used to manage multi-connectivity communication for aUE 115 communicating with a first eNB 105, the device 605, and possiblyone or more other second eNBs 135. The wireless communication managementmodule 620 may also be used to facilitate an allocation of uplinktransmit power between the first eNB 105, the device 605, and possiblyone or more other second eNBs 135.

Referring now to FIG. 7, a block diagram 700 illustrates an example of adevice 605-a usable for wireless communication, in accordance withvarious aspects of the present disclosure. The device 605-a may be anexample of one or more aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,or 6. The device 605-a may also be a processor. The device 605-a mayinclude a receiver module 610, a wireless communication managementmodule 620-a, or a transmitter module 630. Each of these components maybe in communication with each other.

The components of the device 605-a may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Alternatively, the functions may beperformed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each unit may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

The receiver module 610 may be configured similarly to the receivermodule 610 described with reference to FIG. 6. Similarly, thetransmitter module 630 may be configured similarly to the transmittermodule 630 described with reference to FIG. 6.

The wireless communication management module 620-a may be an example ofthe wireless communication management module 620 described withreference to FIG. 6 and may include an eNB connection management module705, an uplink transmit power management module 710, and an uplinkcommunications management module 715.

The eNB connection management module 705 may be used to establish aconnection with a first eNB and a second eNB. Each of the first eNB andthe second eNB may provide radio resources to the UE for respectiveuplink communications. Each of the first eNB and the second eNB may alsoprovide radio resources to the UE 115-b for respective downlinkcommunications. In some cases, the first eNB may be an example of one ormore aspects of one of the first eNBs 105 or the device 605 configuredas a first eNB, as described with reference to FIG. 1, 2, 3, 4, 5, or 6.In some cases, the second eNB may be an example of one or more aspectsof one of the second eNBs 135 or the device 605 configured as a secondeNB, as described with reference to FIG. 1, 2, 3, 4, 5, or 6. In somecases, the first eNB may include a master eNB and the second eNB mayinclude a secondary eNB.

The uplink transmit power management module 710 may be used to receivefrom the first eNB, at the device 605-a, an indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB. The uplink transmit power may in some cases be a maximumuplink transmit power.

When the first eNB or the second eNB operates in a TDD mode, theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB may be based at least in part onan UL/DL configuration of the first eNB or the second eNB. For example,when an eNB operates in a TDD mode, the number of active uplink carrierscan change over time based on the TDD configuration of each cell withinthe eNB. When the number of active uplink carriers used by an eNB isless during a particular time period, more of the total uplink transmitpower available to a UE during the time period may be allocated toanother eNB with which the UE may communicate during the time period.Conversely, more of the total uplink transmit power available to the UEduring the time period may be allocated to an eNB when the number ofactive uplink carriers used by the eNB is greater during a particulartime period.

In some examples, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

In some examples, the uplink transmit power management module 710 maydetermine an allocation of uplink transmit power between a plurality ofcells of the first eNB or the second eNB based on the indicationincluding the allocation of uplink transmit power between the first eNBand at least the second eNB. The allocation of uplink transmit powerbetween the plurality of cells may in some cases be semi-staticallyspecified in the indication (e.g., the first eNB may specify orconfigure an uplink transmit power value for each cell, which uplinktransmit power value may be used by the UE until the UE receives, fromthe first eNB, an adjusted indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB). Theallocation of uplink transmit power between the plurality of cells mayin other cases be semi-statically specified per time index in theindication (e.g., the first eNB may specify or configure multiple uplinktransmit power values for each cell, for each time index, which uplinktransmit power values may be used by the UE until the UE receives, fromthe first eNB, an adjusted indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB).

In some examples, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an allocation of total transmit power, or a percentage oftransmit power, between communications with the first eNB and the secondeNB. In these embodiments, the uplink transmit power management module710 may determine an uplink transmit power for each of a plurality ofcells controlled by the first eNB or the second eNB based on theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB. In some cases, the uplinktransmit power per cell (e.g., the maximum uplink transmit power percell) may be dynamically adjusted by the uplink transmit powermanagement module 710.

The uplink communications management module 715 may be used to transmitthe uplink communications from the device 605-a to the first eNB and thesecond eNB based on the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB.

Referring now to FIG. 8, a block diagram 800 illustrates an example of adevice 605-b usable for wireless communication, in accordance withvarious aspects of the present disclosure. The device 605-b may be anexample of one or more aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,6, or 7. The device 605-b may also be a processor. The device 605-b mayinclude a receiver module 610, a wireless communication managementmodule 620-b, and a transmitter module 630. Each of these components maybe in communication with each other.

The components of the device 605-b may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Alternatively, the functions may beperformed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each unit may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

The receiver module 610 may be configured similarly to the receivermodule 610 described with reference to FIG. 6. Similarly, thetransmitter module 630 may be configured similarly to the transmittermodule 630 described with reference to FIG. 6.

The wireless communication management module 620-b may be an example ofthe wireless communication management module 620 described withreference to FIG. 6 or 7 and may include an eNB connection managementmodule 705-a, an uplink transmit power management module 710-a, anuplink communications management module 715-a, a power headroom reportgeneration module 805, a power headroom report transmission module 810,and an uplink transmit power modification module 815.

The eNB connection management module 705-a may be used to establish aconnection with a first eNB and a second eNB. Each of the first eNB andthe second eNB may provide radio resources to the UE for respectiveuplink communications. Each of the first eNB and the second eNB may alsoprovide radio resources to the UE 115-b for respective downlinkcommunications. In some cases, the first eNB may be an example of one ormore aspects of one of the first eNBs 105 or the device 605 configuredas a first eNB, as described with reference to FIG. 1, 2, 3, 4, 5, or 6.In some cases, the second eNB may be an example of one or more aspectsof one of the second eNBs 135 or the device 605 configured as a secondeNB, as described with reference to FIG. 1, 2, 3, 4, 5, or 6. In somecases, the first eNB may include a master eNB and the second eNB mayinclude a secondary eNB.

The uplink transmit power management module 710-a may be used to receivefrom the first eNB, at the device 605-b, an indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB. The uplink transmit power may in some cases be a maximumuplink transmit power.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB may bebased at least in part on an UL/DL configuration of the first eNB or thesecond eNB. For example, when an eNB operates in a TDD mode, the numberof active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

In some embodiments, the uplink transmit power management module 710-amay determine an allocation of uplink transmit power between a pluralityof cells of the first eNB or the second eNB based on the indicationincluding the allocation of uplink transmit power between the first eNBand at least the second eNB. The allocation of uplink transmit powerbetween the plurality of cells may in some cases be semi-staticallyspecified in the indication (e.g., the first eNB may specify orconfigure an uplink transmit power value for each cell, which uplinktransmit power value may be used by the UE until the UE receives, fromthe first eNB, an adjusted indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB). Theallocation of uplink transmit power between the plurality of cells mayin other cases be semi-statically specified per time index in theindication (e.g., the first eNB may specify or configure multiple uplinktransmit power values for each cell, for each time index, which uplinktransmit power values may be used by the UE until the UE receives, fromthe first eNB, an adjusted indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB).

In some embodiments, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an allocation of total transmit power, or a percentage of totaltransmit power, between communications with the first eNB and the secondeNB. In these embodiments, the uplink transmit power management module710-a may determine an uplink transmit power for each of a plurality ofcells controlled by the first eNB or the second eNB based on theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB. In some cases, the uplinktransmit power per cell (e.g., the maximum uplink transmit power percell) may be dynamically adjusted by the uplink transmit powermanagement module 710-a.

The uplink communications management module 715-a may be used totransmit the uplink communications from the device 605-b to the firsteNB and the second eNB based on the indication including an allocationof uplink transmit power between the first eNB and at least the secondeNB.

The power headroom report generation module 805 may be used to trigger apower headroom report at the device 605-b. In some embodiments, thepower headroom report generation module 805 may trigger a power headroomreport for an eNB (e.g., the first eNB or the second eNB) based on acondition of the eNB or a neighbor eNB (e.g., an eNB other than the eNBfor which the power headroom report is triggered). By way of example,the condition of the eNB or the neighbor eNB may be a determination thatan uplink transmit power of the device 605-b for the eNB or the neighboreNB has crossed a threshold. In some cases, the threshold may include amaximum uplink power for the eNB. By way of further example, thecondition of the eNB or the neighbor eNB may be a measured pathloss(e.g., a pathloss variation satisfying a threshold) of the eNB or theneighbor eNB. By way of still further example, the condition of the eNBor the neighbor eNB may be a determination that the eNB or the neighboreNB has activated an uplink cell.

The power headroom report generation module 805 may also be used togenerate a power headroom report at the device 605-b. The power headroomreport may include power headroom information for both the first eNB andthe second eNB. The inclusion of power headroom information for both thefirst eNB and the second eNB may reduce power headroom report overheadand enable an eNB to estimate the total uplink transmit power used bythe device 605-b. In some examples, the power headroom information maybe computed using Equation 1.

The power headroom report transmission module 810 may be used totransmit a power headroom report to the first eNB or the second eNB. Insome embodiments, a power headroom report may be automaticallytransmitted to an eNB for which the power headroom report is triggered.In other embodiments, a power headroom report may be transmitted to aneNB for which the power headroom report is triggered in response to atriggering message received from the eNB. In the latter embodiments, andby way of example, a power headroom report triggered for the first eNBmay be transmitted to the first eNB in response to a triggering messagereceived from the first eNB.

In some cases, the power headroom report transmission module 810 maytransmit a power headroom report to the eNB for which the power headroomreport was triggered (e.g., a power headroom report triggered for thefirst eNB may be transmitted to the first eNB). In other cases, thepower headroom report transmission module 810 may transmit a powerheadroom report to the eNB for which the power headroom report wastriggered, as well as a neighbor eNB (e.g., a power headroom reporttriggered for the first eNB may be transmitted to the first eNB and thesecond eNB). In the latter cases, the power headroom report transmissionmodule 810 may in some cases transmit a power headroom report to aneighbor eNB based on a determination that uplink resources areallocated to the UE for an uplink transmission to the neighbor eNB.

After the power headroom report transmission module 810 transmits apower headroom report to an eNB, the uplink transmit power managementmodule 710-a may be used to receive a second indication including anallocation of uplink transmit power from the first eNB. The secondindication including an allocation of uplink transmit power may changethe uplink transmit power allocated to the first eNB or the second eNB.After receiving the second indication including an allocation of uplinktransmit power, the power headroom report generation module 805 may beused to determine power headroom for the first eNB and the second eNBwith respect to the uplink transmit power allocated to the first eNB orthe second eNB in the second indication.

The uplink transmit power modification module 815 may be used to modifyan allocation of total uplink transmit power between the first eNB andthe second eNB (or an allocation of uplink transmit power betweencells), when possible and useful to transmit uplink communications fromthe UE to the first eNB or the second eNB. In some cases, the uplinktransmit power modification module 815 may modify an allocation ofuplink transmit power by borrowing uplink transmit power allocated toone eNB or cell and re-allocating the borrowed uplink transmit power toanother eNB or cell. The modification of the allocation of uplinktransmit power may in some cases be based on a priority of uplink dataor control information for one of the eNBs (e.g., the first eNB or thesecond eNB) with respect to the other of the eNBs. The modification mayalso or alternately be based on a priority of uplink data or controlinformation for a cell. The modification may also or alternately bebased on non-use of an uplink by an eNB or cell.

Following modification of the allocation of uplink transmit powerbetween the first eNB and the second eNB, a power headroom report may begenerated using the power headroom report generation module 805. Thepower headroom report may include power headroom information for boththe first eNB and the second eNB. The inclusion of power headroominformation for both the first eNB and the second eNB may reduce powerheadroom report overhead and enable an eNB to estimate the total uplinktransmit power used by the device 605-b. In some examples, the powerheadroom information may be computed using Equation 1.

The power headroom report triggered by modification of the allocation ofuplink transmit power between the first eNB and the second eNB may betransmitted to the first eNB or the second eNB. In some cases, the powerheadroom report transmission module 810 may transmit a power headroomreport to an eNB that received power during modification of anallocation of uplink transmit power. Such a power headroom report mayinclude negative power headroom information. In other cases, the powerheadroom report transmission module 810 may transmit a power headroomreport to an eNB from which power was borrowed during modification of anallocation of uplink transmit power. The latter power headroom reportmay subtract the borrowed power from the configured maximum power for aneNB or cell. In the case of power headroom information per cell, thepower headroom information may be computed using Equation 2.

Referring now to FIG. 9, a block diagram 900 illustrates an example of adevice 605-c usable for wireless communication, in accordance withvarious aspects of the present disclosure. The device 605-c may be anexample of one or more aspects of one of the first eNBs 105 or thedevice 605 configured as a first eNB, as described with reference toFIG. 1, 2, 3, 4, 5, or 6. The device 605-c may also be a processor. Thedevice 605-c may include a receiver module 610, a wireless communicationmanagement module 620-c, and a transmitter module 630. Each of thesecomponents may be in communication with each other.

The components of the device 605-c may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Alternatively, the functions may beperformed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each unit may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

The receiver module 610 may be configured similarly to the receivermodule 610 described with reference to FIG. 6. Similarly, thetransmitter module 630 may be configured similarly to the transmittermodule 630 described with reference to FIG. 6.

The wireless communication management module 620-c may be an example ofthe wireless communication management module 620 described withreference to FIG. 6 and may include a UE multi-connectivity managementmodule 905, an uplink transmit power determination module 910, and anuplink transmit power communication module 915.

The UE multi-connectivity management module 905 may be used tocoordinate, for a UE, multi-connectivity communication with at least thedevice 605-c and a second eNB. In some cases, the UE may be an exampleof one or more aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,6, 7, or 8. In some cases, the second eNB may be an example of one ormore aspects of one of the second eNBs 135 or the device 605 configuredas a second eNB, as described with reference to FIG. 1, 2, 3, 4, 5, or6. In some cases, the device 605-c may include a master eNB and thesecond eNB may include a secondary eNB.

The uplink transmit power determination module 910 may be used todetermine, for the UE, an allocation of uplink transmit power betweenthe device 605-c and at least the second eNB. The uplink transmit powermay in some cases be a maximum uplink transmit power.

In some examples, the uplink transmit power determination module 910 maydetermine an allocation of uplink transmit power between a plurality ofcells of the device 605-c based on the indication including theallocation of uplink transmit power between the device 605-c and atleast the second eNB. The allocation of uplink transmit power betweenthe plurality of cells may in some cases be semi-statically specified inthe indication (e.g., the device 605-c may specify or configure anuplink transmit power value for each cell, which uplink transmit powervalue may be used by the UE until the UE receives, from the device605-c, an adjusted indication including an allocation of uplink transmitpower between the device 605-c and at least the second eNB). Theallocation of uplink transmit power between the plurality of cells mayin other cases be semi-statically specified per time index in theindication (e.g., the device 605-c may specify or configure multipleuplink transmit power values for each cell, for each time index, whichuplink transmit power values may be used by the UE until the UEreceives, from the device 605-c, an adjusted indication including anallocation of uplink transmit power between the device 605-c and atleast the second eNB).

The uplink transmit power communication module 915 may be used totransmit an indication including the allocation of uplink transmit powerallocation to the UE.

In some examples, such as when the device 605-c or the second eNBoperates in a TDD mode, the indication including the allocation ofuplink transmit power between the device 605-c and at least the secondeNB may be based at least in part on an UL/DL configuration of thedevice 605-c or the second eNB. For example, when an eNB operates in aTDD mode, the number of active uplink carriers can change over timebased on the TDD configuration of each cell within the eNB. When thenumber of active uplink carriers used by an eNB is less during aparticular time period, more of the total uplink transmit poweravailable to a UE during the time period may be allocated to another eNBwith which the UE may communicate during the time period. Conversely,more of the total uplink transmit power available to the UE during thetime period may be allocated to an eNB when the number of active uplinkcarriers used by the eNB is greater during a particular time period.

In some examples, the indication including the allocation of uplinktransmit power between the device 605-c and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the device 605-c or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

Referring now to FIG. 10, a block diagram 1000 illustrates an example ofa device 605-d usable for wireless communication, in accordance withvarious aspects of the present disclosure. The device 605-d may be anexample of one or more aspects of one of the first eNBs 105 or thedevice 605 configured as a first eNB, as described with reference toFIG. 1, 2, 3, 4, 5, or 6. The device 605-d may also be a processor. Thedevice 605-d may include a receiver module 610, a wireless communicationmanagement module 620-d, and a transmitter module 630. Each of thesecomponents may be in communication with each other.

The components of the device 605-d may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Alternatively, the functions may beperformed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each unit may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

The receiver module 610 may be configured similarly to the receivermodule 610 described with reference to FIG. 6. Similarly, thetransmitter module 630 may be configured similarly to the transmittermodule 630 described with reference to FIG. 6.

The wireless communication management module 620-d may be an example ofthe wireless communication management module 620 described withreference to FIG. 6 and may include a UE multi-connectivity managementmodule 905-a, an uplink transmit power determination module 910-a, anuplink transmit power communication module 915-a, and a power headroomreport processing module 1005.

The UE multi-connectivity management module 905-a may be used tocoordinate, for a UE, multi-connectivity communication with at least thedevice 605-d and a second eNB. In some cases, the UE may be an exampleof one or more aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,6, 7, or 8. In some cases, the second eNB may be an example of one ormore aspects of one of the second eNBs 135 or the device 605 configuredas a second eNB, as described with reference to FIG. 1, 2, 3, 4, 5, or6. In some cases, the device 605-d may include a master eNB and thesecond eNB may include a secondary eNB.

The uplink transmit power determination module 910-a may be used todetermine, for the UE, an allocation of uplink transmit power betweenthe device 605-d and at least the second eNB. The uplink transmit powermay in some cases be a maximum uplink transmit power.

In some embodiments, the uplink transmit power determination module910-a may determine an allocation of uplink transmit power between aplurality of cells of the device 605-d based on the indication includingthe allocation of uplink transmit power between the device 605-d and atleast the second eNB. The allocation of uplink transmit power betweenthe plurality of cells may in some cases be semi-statically specified inthe indication (e.g., the device 605-d may specify or configure anuplink transmit power value for each cell, which uplink transmit powervalue may be used by the UE until the UE receives, from the device605-d, an adjusted indication including an allocation of uplink transmitpower between the device 605-d and at least the second eNB). Theallocation of uplink transmit power between the plurality of cells mayin other cases be semi-statically specified per time index in theindication (e.g., the device 605-d may specify or configure multipleuplink transmit power values for each cell, for each time index, whichuplink transmit power values may be used by the UE until the UEreceives, from the device 605-d, an adjusted indication including anallocation of uplink transmit power between the device 605-d and atleast the second eNB).

The uplink transmit power communication module 915-a may be used totransmit an indication including the allocation of uplink transmit powerallocation to the UE.

In some embodiments, such as when the device 605-d or the second eNBoperates in a TDD mode, the indication including the allocation ofuplink transmit power between the device 605-d and at least the secondeNB may be based at least in part on an UL/DL configuration of thedevice 605-d or the second eNB. For example, when an eNB operates in aTDD mode, the number of active uplink carriers can change over timebased on the TDD configuration of each cell within the eNB. When thenumber of active uplink carriers used by an eNB is less during aparticular time period, more of the total uplink transmit poweravailable to a UE during the time period may be allocated to another eNBwith which the UE may communicate during the time period. Conversely,more of the total uplink transmit power available to the UE during thetime period may be allocated to an eNB when the number of active uplinkcarriers used by the eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the device 605-d and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the device 605-d or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

The power headroom report processing module 1005 may be used to receivea power headroom report including power headroom information for atleast the device 605-d and the second eNB. In some cases, the powerheadroom report may be received in response to at least one of: anuplink transmit power of the UE for the second eNB, a measured pathlossvariation for the second eNB, or the second eNB activating an uplinkcell, as described with reference to the power headroom reportgeneration module 805 described with reference to FIG. 8. In some cases,the power headroom report may be received in response to the device605-b sending a triggering message (e.g., a request for a power headroomreport) to the UE.

The power headroom report processing module 1005 may optionally transmitthe power headroom report to the second eNB.

In some embodiments, a power headroom report may indicate that the UEhas modified the allocation of uplink transmit power between the device605-d and the second eNB, and the power headroom report processingmodule 1005 may be used to determine, based on the power headroomreport, that the UE has modified the allocation of uplink transmit powerbetween the device 605-d and the second eNB. In other embodiments, thepower headroom report may not indicate that the UE has modified theallocation of uplink transmit power between the device 605-d and thesecond eNB.

In some cases, the UL transmit power determination module 910-a may beused to adjust the allocation of uplink transmit power between thedevice 605-d and the second eNB for the UE based on the power headroomreport. In some cases, the adjustment may be based on a modification bythe UE to the allocation of uplink transmit power between the first eNBand the second eNB. In some cases, the UL transmit power communicationmodule 915-a may be used to transmit the adjusted allocation of uplinktransmit power to at least one of the UE or the second eNB.

In some embodiments of the device 605-d, an adjustment of the allocationof uplink transmit power between the device 605-d and the second eNB forthe UE may also or alternately be made based on a message received atthe device 605-d from the second eNB. The message may include the powerheadroom report of the UE or information generated by the second eNB.

In some embodiments of the device 605-d, the wireless communicationmanagement module 620-d may schedule communications (e.g., downlink oruplink communications) with the UE. The communications between the UEand the device 605-d may be scheduled independently from communicationsbetween the UE and the second eNB.

FIG. 11 shows a block diagram 1100 of a UE 115-e configured for wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 115-e may have various configurations and may beincluded or be part of a personal computer (e.g., a laptop computer,netbook computer, tablet computer, etc.), a cellular telephone, a PDA, adigital video recorder (DVR), an internet appliance, a gaming console,an e-reader, etc. The UE 115-e may in some cases have an internal powersupply (not shown), such as a small battery, to facilitate mobileoperation. In some embodiments, the UE 115-e may be an example of one ormore aspects of one of the UEs 115 or the device 605 configured as a UE,as described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, or 8. The UE115-e may be configured to implement at least some of the UE featuresand functions described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, or8. The UE 115-e may be configured to communicate with one of the firsteNBs 105 or the device 605 configured as a first eNB, or with one ormore of the second eNBs 135 or the device 605 configured as a secondeNB, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 9, or 10.

The UE 115-e may include a processor module 1110, memory 1120, at leastone transceiver module (represented by transceiver module(s) 1130), atleast one antenna (represented by antenna(s) 1140), and a wirelesscommunication management module 620-e. Each of these components may bein communication with each other, directly or indirectly, over one ormore buses 1135.

The memory 1120 may include random access memory (RAM) or read-onlymemory (ROM). The memory 1120 may store computer-readable,computer-executable code 1125 containing instructions that areconfigured to, when executed, cause the processor module 1110 to performvarious functions described herein for managing wireless communication.Alternatively, the code 1125 may not be directly executable by theprocessor module 1110 but be configured to cause the UE 115-e (e.g.,when compiled and executed) to implement various of the UE features andfunctions described herein.

The processor module 1110 may include an intelligent hardware device,e.g., a CPU, a microcontroller, an ASIC, etc. The processor module 1110may process information received through the transceiver module(s) 1130or information to be sent to the transceiver module(s) 1130 fortransmission via the antenna(s) 1140. The processor module 1110 may alsohandle, alone or in connection with the wireless communicationmanagement module 620-e, various aspects of managing uplink transmitpower for communications with a first eNB and a second eNB.

The transceiver module(s) 1130 may include a modem configured tomodulate packets and provide the modulated packets to the antenna(s)1140 for transmission, and to demodulate packets received from theantenna(s) 1140. The transceiver module(s) 1130 may in some cases beimplemented as one or more transmitter modules and one or more separatereceiver modules. The transceiver module(s) 1130 may be configured tocommunicate bi-directionally, via the antenna(s) 1140, with one or moreeNBs 105 or 135, or other UEs 115. While the UE 115-e may include asingle antenna, there may be embodiments in which the UE 115-e mayinclude multiple antennas 1140.

The wireless communication management module 620-e may be an example ofone or more aspects of the wireless communication management module 620described with reference to FIG. 6, 7, or 8 and may be configured toperform or control some or all of the wireless communication managementfunctions described with reference to FIG. 3, 4, 5, 6, 7, or 8.

According to the architecture of FIG. 11, the UE 115-e may furtherinclude a state module 1150. The state module 1150 may reflect andcontrol the current device state (e.g., context, authentication, basestation association, or other connectivity issues).

By way of example, each of the wireless communication management module620-e or the state module 1150, or a portion of one or both modules, maybe a component of the UE 115-e in communication with some or all of theother components of the UE 115-e via one or more buses 1135.Alternatively, functionality of the wireless communication managementmodule 620-e or the state module 1150 may be implemented using aprocessor, or some or all of the functionality of the wirelesscommunication management module 620-e or the state module 1150 may beimplemented by the code 1125 or the processor module 1110 or inconnection with the processor module 1110.

The components of the UE 115-e may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each component may also be implemented, inwhole or in part, with instructions embodied in a memory, formatted tobe executed by one or more general or application-specific processors.Each of the noted modules may be a means for performing one or morefunctions related to operation of the UE 115-e.

FIG. 12 shows a block diagram 1200 illustrating an eNB 105-e configuredfor wireless communication, in accordance with various aspects of thepresent disclosure. In some embodiments, the eNB 105-e may be an exampleof one or more aspects of one of the first eNBs 105 or the device 605configured as a first eNB, or aspects of one of the second eNBs 135, asdescribed with reference to FIG. 1, 2, 3, 4, 5, 6, 9, or 10. The eNB105-e may be configured to implement at least some of the first eNB orsecond eNB features and functions described with reference to FIG. 1, 2,3, 4, 5, 6, 9, or 10. The eNB 105-e may be configured to communicatewith one or more of the UEs 115 or the device 605 configured as a UE, asdescribed with reference to FIG. 1, 2, 3, 4, 5, 6, 7, or 8. The eNB105-e may also be configured to communicate with a first eNB or a secondeNB 135, as described with reference to FIG. 2, 3, 4, 5, 6, 7, 8, 9, 10,or 11.

The eNB 105-e may include a processor module 1210, memory 1220, at leastone transceiver module (represented by transceiver module(s) 1230), atleast one antenna (represented by antenna(s) 1240), and a wirelesscommunication management module 620-f. The eNB 105-e may also includeone or more of an eNB communications module 1250 and a networkcommunications module 1260. Each of these components may be incommunication with each other, directly or indirectly, over one or morebuses 1235.

The memory 1220 may include RAM or ROM. The memory 1220 may storecomputer-readable, computer-executable code 1225 containing instructionsthat are configured to, when executed, cause the processor module 1210to perform various functions described herein for managing wirelesscommunication. Alternatively, the code 1225 may not be directlyexecutable by the processor module 1210 but be configured to cause theeNB 105-e (e.g., when compiled and executed) to perform various of theeNB features and functions described herein.

The processor module 1210 may include an intelligent hardware device,e.g., a CPU, a microcontroller, an ASIC, etc. The processor module 1210may process information received through the transceiver module(s) 1230,the eNB communications module 1250, or the network communications module1260. The processor module 1210 may also process information to be sentto the transceiver module(s) 1230 for transmission through theantenna(s) 1240, to the eNB communications module 1250 for transmissionto one or more other eNBs 105-f and 105-g, or to the networkcommunications module 1260 for transmission to a core network 130-a,which may be an example of one or more aspects of the core network 130described with reference to FIG. 1. The processor module 1210 mayhandle, alone or in connection with the wireless communicationmanagement module 620-f, various aspects of managing uplink transmitpower for one or more UEs communicating with the eNB 105-e and at leastone other eNB.

The transceiver module(s) 1230 may include a modem configured tomodulate packets and provide the modulated packets to the antenna(s)1240 for transmission, and to demodulate packets received from theantenna(s) 1240. The transceiver module(s) 1230 may in some cases beimplemented as one or more transmitter modules and one or more separatereceiver modules. The transceiver module(s) 1240 may be configured tocommunicate bi-directionally, via the antenna(s) 1240, with one or moreUEs 115. The eNB 105-e may typically include multiple antennas 1240(e.g., an antenna array). The eNB 105-e may communicate with the corenetwork 130-a through the network communications module 1260. The eNB105-e may also communicate with other eNBs, such as the eNBs 105-f and105-g, using the eNB communications module 1250.

The wireless communication management module 620-f may be an example ofone or more aspects of the wireless communication management module 620described with reference to FIG. 6, 9, or 10 and may be configured toperform or control some or all of the wireless communication managementfunctions described with reference to FIG. 3, 4, 5, 6, 9, or 10. By wayof example, the wireless communication management module 620-f, or aportion thereof, may be a component of the eNB 105-e in communicationwith some or all of the other components of the eNB 105-e via one ormore buses 1235. Alternatively, functionality of the wirelesscommunication management module 620-f may be implemented using aprocessor, or some or all of the functionality of the wirelesscommunication management module 620-f may be implemented by the code1225 or the processor module 1210 or in connection with the processormodule 1210.

The components of the eNB 105-e may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other embodiments, other types ofintegrated circuits may be used (e.g., Structured/Platform ASICs, FPGAs,and other Semi-Custom ICs), which may be programmed in any manner knownin the art. The functions of each component may also be implemented, inwhole or in part, with instructions embodied in a memory, formatted tobe executed by one or more general or application-specific processors.Each of the noted modules may be a means for performing one or morefunctions related to operation of the eNB 105-e. The components of theENB 105-e may in some cases be replicated or distributed amongst morethan one base station.

FIG. 13 is a flow chart illustrating a method 1300 of wirelesscommunication by a UE, in accordance with various aspects of the presentdisclosure. For clarity, the method 1300 is described below withreference to aspects of one of the UEs 115 or the device 605 configuredas a UE, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, or1, aspects of one of the first eNBs 105 or the device 605 configured asa first eNB, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 9,10, or 12, or aspects of one of the second eNBs 135 or the device 605configured as a second eNB, as described with reference to FIG. 1, 2, 3,4, 5, 6, or 12. In one implementation, the wireless communicationmanagement module 620 described with reference to FIG. 6, 7, 8, or 11may execute one or more sets of codes to control the functional elementsof a UE 115 or the device 605 configured as a UE to perform thefunctions described below.

At block 1305, a connection with a first eNB and a second eNB may beestablished, wherein each of the first eNB and the second eNB provideradio resources to the UE for respective uplink communications. Each ofthe first eNB and the second eNB may also provide radio resources to theUE 115-b for respective downlink communications. In some cases, thefirst eNB may include a master eNB and the second eNB may include asecondary eNB. The operation(s) at block 1305 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the eNB connection managementmodule 705 described with reference to FIG. 7 or 8.

At block 1310, an indication of an allocation of uplink transmit powerbetween the first eNB and at least the second eNB may be received fromthe first eNB. The indication of the allocation of uplink transmit powermay in some cases include an indication of a maximum uplink transmitpower allocated to each of the first eNB and at least the second eNB.The operation(s) at block 1310 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 7, 8, or 11, or the uplink transmit power management module 710described with reference to FIG. 7 or 8.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB may bebased at least in part on an UL/DL configuration of the first eNB or thesecond eNB. For example, when an eNB operates in a TDD mode, the numberof active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

In some embodiments, the UE may determine an allocation of uplinktransmit power between a plurality of cells of the first eNB or thesecond eNB based on the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB. Theallocation of uplink transmit power between the plurality of cells mayin some cases be semi-statically specified in the indication (e.g., thefirst eNB may specify or configure an uplink transmit power value foreach cell, which uplink transmit power value may be used by the UE untilthe UE receives, from the first eNB, an adjusted indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB). The allocation of uplink transmit power between theplurality of cells may in other cases be semi-statically specified pertime index in the indication (e.g., the first eNB may specify orconfigure multiple uplink transmit power values for each cell, for eachtime index, which uplink transmit power values may be used by the UEuntil the UE receives, from the first eNB, an adjusted indicationincluding an allocation of uplink transmit power between the first eNBand at least the second eNB).

In some embodiments, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an allocation of total transmit power between communicationswith the first eNB and the second eNB. In these embodiments, the UE maydetermine, at the UE, an uplink transmit power for each of a pluralityof cells controlled by the first eNB or the second eNB based on theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB. In some cases, the uplinktransmit power per cell (e.g., the maximum uplink transmit power percell) may be dynamically adjusted at the UE.

At block 1315, the uplink communications may be transmitted from the UEto the first eNB and the second eNB based on the indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB. The operation(s) at block 1315 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the uplink communicationsmanagement module 715 described with reference to FIG. 7 or 8.

Therefore, the method 1300 may be used for wireless communication. Itshould be noted that the method 1300 is just one implementation and thatthe operations of the method 1300 may be rearranged or otherwisemodified such that other implementations are possible.

FIG. 14 is a flow chart illustrating a method 1400 of wirelesscommunication by a UE, in accordance with various aspects of the presentdisclosure. For clarity, the method 1400 is described below withreference to aspects of one of the UEs 115 or the device 605 configuredas a UE, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, or1, aspects of one of the first eNBs 105 or the device 605 configured asa first eNB, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 9,10, or 12, or aspects of one of the second eNBs 135 or the device 605configured as a second eNB, as described with reference to FIG. 1, 2, 3,4, 5, 6, or 12. In one implementation, the wireless communicationmanagement module 620 described with reference to FIG. 6, 7, 8, or 11may execute one or more sets of codes to control the functional elementsof a UE 115 or the device 605 configured as a UE to perform thefunctions described below.

At block 1405, a connection with a first eNB and a second eNB may beestablished, wherein each of the first eNB and the second eNB provideradio resources to the UE for respective uplink communications. Each ofthe first eNB and the second eNB may also provide radio resources to theUE 115-b for respective downlink communications. In some cases, thefirst eNB may include a master eNB and the second eNB may include asecondary eNB. The operation(s) at block 1405 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the eNB connection managementmodule 705 described with reference to FIG. 7 or 8.

At block 1410, an indication of an allocation of uplink transmit powerbetween the first eNB and at least the second eNB may be received fromthe first eNB. The indication of the allocation of uplink transmit powermay in some cases include an indication of a maximum uplink transmitpower, or a percentage of uplink transmit power, allocated to each ofthe first eNB and at least the second eNB. The operation(s) at block1410 may be performed or managed using the wireless communicationmanagement module 620 described with reference to FIG. 6, 7, 8, or 11,or the uplink transmit power management module 710 described withreference to FIG. 7 or 8.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB may bebased at least in part on an UL/DL configuration of the first eNB or thesecond eNB. For example, when an eNB operates in a TDD mode, the numberof active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

In some embodiments, the UE may determine an allocation of uplinktransmit power between a plurality of cells of the first eNB or thesecond eNB based on the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB. Theallocation of uplink transmit power between the plurality of cells mayin some cases be semi-statically specified in the indication (e.g., thefirst eNB may specify or configure an uplink transmit power value foreach cell, which uplink transmit power value may be used by the UE untilthe UE receives, from the first eNB, an adjusted indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB). The allocation of uplink transmit power between theplurality of cells may in other cases be semi-statically specified pertime index in the indication (e.g., the first eNB may specify orconfigure multiple uplink transmit power values for each cell, for eachtime index, which uplink transmit power values may be used by the UEuntil the UE receives, from the first eNB, an adjusted indicationincluding an allocation of uplink transmit power between the first eNBand at least the second eNB).

In some embodiments, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an allocation of total transmit power between communicationswith the first eNB and the second eNB. In these embodiments, the UE maydetermine, at the UE, an uplink transmit power for each of a pluralityof cells controlled by the first eNB or the second eNB based on theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB. In some cases, the uplinktransmit power per cell (e.g., the maximum uplink transmit power percell) may be dynamically adjusted at the UE.

At block 1415, the uplink communications may be transmitted from the UEto the first eNB and the second eNB based on the indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB. The operation(s) at block 1415 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the uplink communicationsmanagement module 715 described with reference to FIG. 7 or 8.

At block 1420, a power headroom report at the UE may be triggered. Insome embodiments, a power headroom report for an eNB (e.g., the firsteNB or the second eNB) may be triggered based on a condition of the eNBor a neighbor eNB (e.g., an eNB other than the eNB for which the powerheadroom report is triggered). By way of example, the condition of theeNB or the neighbor eNB may be a determination that an uplink transmitpower of the UE for the eNB or the neighbor eNB has crossed a threshold.In some cases, the threshold may include a maximum uplink power for theeNB. By way of further example, the condition of the eNB or the neighboreNB may be a measured pathloss (e.g., a pathloss variation satisfying athreshold) of the eNB or the neighbor eNB. By way of still furtherexample, the condition of the eNB or the neighbor eNB may be adetermination that the eNB or the neighbor eNB has activated an uplinkcell.

At block 1425, a power headroom report may be generated at the UE. Thepower headroom report may include power headroom information for boththe first eNB and the second eNB. The inclusion of power headroominformation for both the first eNB and the second eNB may reduce powerheadroom report overhead and enable an eNB to estimate the total uplinktransmit power used by the UE. In some examples, the power headroominformation may be computed using Equation 1.

The operation(s) at block 1420 or 1425 may be performed or managed usingthe wireless communication management module 620 described withreference to FIG. 6, 7, 8, or 11, or the power headroom reportgeneration module 805 described with reference to FIG. 8.

In some embodiments, a power headroom report may be automaticallytransmitted to an eNB for which the power headroom report is triggered.In other embodiments, a power headroom report may be transmitted to aneNB for which the power headroom report is triggered in response to atriggering message received from the eNB at block 1430. In the latterembodiments, and by way of example, a power headroom report triggeredfor the first eNB may be transmitted to the first eNB in response to atriggering message received from the first eNB.

At block 1435, a power headroom report may be transmitted to the firsteNB or the second eNB. In some cases, a power headroom report may betransmitted to the eNB for which the power headroom report was triggered(e.g., a power headroom report triggered for the first eNB may betransmitted to the first eNB). In other cases, a power headroom reportmay be transmitted to the eNB for which the power headroom report wastriggered, as well as a neighbor eNB (e.g., a power headroom reporttriggered for the first eNB may be transmitted to the first eNB and thesecond eNB). In the latter cases, the UE may in some cases transmit apower headroom report to a neighbor eNB based on a determination thatuplink resources are allocated to the UE for an uplink transmission tothe neighbor eNB. The operation(s) at block 1435 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the power headroom reporttransmission module 810 described with reference to FIG. 8.

At block 1440, a second indication including an allocation of uplinktransmit power may be received from the first eNB. The second indicationmay be received in response to the power headroom report transmitted atblock 1435. The second indication including an allocation of uplinktransmit power may change the uplink transmit power allocated to thefirst eNB or the second eNB. The operation(s) at block 1440 may beperformed or managed using the wireless communication management module620 described with reference to FIG. 6, 7, 8, or 11, or the uplinktransmit power management module 710 described with reference to FIG. 7or 8.

At block 1445, and after receiving the second indication including anallocation of uplink transmit power, the UE may determine power headroomfor the first eNB and the second eNB with respect to the uplink transmitpower allocated to the first eNB or the second eNB in the secondindication including an allocation of uplink transmit power. Theoperation(s) at block 1445 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 7, 8, or 11, or the power headroom report generation module 805described with reference to FIG. 8.

Therefore, the method 1400 may be used for wireless communication. Itshould be noted that the method 1400 is just one implementation and thatthe operations of the method 1400 may be rearranged or otherwisemodified such that other implementations are possible.

FIG. 15 is a flow chart illustrating a method 1500 of wirelesscommunication by a UE, in accordance with various aspects of the presentdisclosure. For clarity, the method 1500 is described below withreference to aspects of one of the UEs 115 or the device 605 configuredas a UE, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, or1, aspects of one of the first eNBs 105 or the device 605 configured asa first eNB, as described with reference to FIG. 1, 2, 3, 4, 5, 6, 9,10, or 12, or aspects of one of the second eNBs 135 or the device 605configured as a second eNB, as described with reference to FIG. 1, 2, 3,4, 5, 6, or 12. In one implementation, the wireless communicationmanagement module 620 described with reference to FIG. 6, 7, 8, or 11may execute one or more sets of codes to control the functional elementsof a UE 115 or the device 605 configured as a UE to perform thefunctions described below.

At block 1505, a connection with a first eNB and a second eNB may beestablished, wherein each of the first eNB and the second eNB provideradio resources to the UE for respective uplink communications. Each ofthe first eNB and the second eNB may also provide radio resources to theUE 115-b for respective downlink communications. In some cases, thefirst eNB may include a master eNB and the second eNB may include asecondary eNB. The operation(s) at block 1505 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the eNB connection managementmodule 705 described with reference to FIG. 7 or 8.

At block 1510, an indication including an allocation of uplink transmitpower between the first eNB and at least the second eNB may be receivedfrom the first eNB. The indication of the allocation of uplink transmitpower may in some cases include an indication of a maximum uplinktransmit power allocated to each of the first eNB and at least thesecond eNB. The operation(s) at block 1510 may be performed or managedusing the wireless communication management module 620 described withreference to FIG. 6, 7, 8, or 11, or the uplink transmit powermanagement module 710 described with reference to FIG. 7 or 8.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB may bebased at least in part on an UL/DL configuration of the first eNB or thesecond eNB. For example, when an eNB operates in a TDD mode, the numberof active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

In some embodiments, the UE may determine an allocation of uplinktransmit power between a plurality of cells of the first eNB or thesecond eNB based on the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB. Theallocation of uplink transmit power between the plurality of cells mayin some cases be semi-statically specified in the indication (e.g., thefirst eNB may specify or configure an uplink transmit power value foreach cell, which uplink transmit power value may be used by the UE untilthe UE receives, from the first eNB, an adjusted indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB). The allocation of uplink transmit power between theplurality of cells may in other cases be semi-statically specified pertime index in the indication (e.g., the first eNB may specify orconfigure multiple uplink transmit power values for each cell, for eachtime index, which uplink transmit power values may be used by the UEuntil the UE receives, from the first eNB, an adjusted indicationincluding an allocation of uplink transmit power between the first eNBand at least the second eNB).

In some embodiments, the indication including an allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an allocation of total transmit power between communicationswith the first eNB and the second eNB. In these embodiments, the UE maydetermine, at the UE, an uplink transmit power for each of a pluralityof cells controlled by the first eNB or the second eNB based on theindication including the allocation of uplink transmit power between thefirst eNB and at least the second eNB. In some cases, the uplinktransmit power per cell (e.g., the maximum uplink transmit power percell) may be dynamically adjusted at the UE.

At block 1515, the uplink communications may be transmitted from the UEto the first eNB and the second eNB based on the indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB. The operation(s) at block 1515 may be performed ormanaged using the wireless communication management module 620 describedwith reference to FIG. 6, 7, 8, or 11, or the uplink communicationsmanagement module 715 described with reference to FIG. 7 or 8.

At block 1520, an allocation of total uplink transmit power between thefirst eNB and the second eNB (or an allocation of uplink transmit powerbetween cells) may be modified by the UE. In some cases, the UE maymodify an allocation of total uplink transmit power by borrowing uplinktransmit power allocated to one eNB or cell and re-allocating theborrowed uplink transmit power to another eNB or cell. The modificationof the allocation of total uplink transmit power may in some cases bebased on a priority of uplink data or control information for one of theeNBs (e.g., the first eNB or the second eNB) with respect to the otherof the eNBs. The modification may also or alternately be based on apriority of uplink data or control information for a cell. Themodification may also or alternately be based on non-use of an uplink byan eNB or cell.

At block 1525, a power headroom report at the UE may be triggered basedon the modification by the UE of the allocation of uplink transmit powerbetween the first eNB and the second eNB (or between cells of one ormore of the first eNB and the second eNB). In some cases, the powerheadroom report may include an indication that an uplink transmit powerfor one of the first eNB or the second eNB has exceeded a maximumtransmit power allocated to that eNB.

At block 1530, a power headroom report may be generated at the UE. Thepower headroom report may include power headroom information for boththe first eNB and the second eNB. The inclusion of power headroominformation for both the first eNB and the second eNB may reduce powerheadroom report overhead and enable an eNB to estimate the total uplinktransmit power used by the UE. In some examples, the power headroominformation may be computed using Equation 1.

At block 1535, a power headroom report may be transmitted to the firsteNB or the second eNB. In some cases, a power headroom report may betransmitted to an eNB that received power during modification of anallocation of uplink transmit power. Such a power headroom report mayinclude negative power headroom information. In other cases, a powerheadroom report may be transmitted to an eNB from which power wasborrowed during modification of an allocation of uplink transmit power.The latter power headroom report may subtract the borrowed power fromthe configured maximum power for an eNB or cell. In the case of powerheadroom information per cell, the power headroom information may becomputed using Equation 2.

At block 1540, a second indication including an allocation of uplinktransmit power may be received from the first eNB, in response to themodification by the UE of the allocation of uplink transmit power.

Therefore, the method 1500 may be used for wireless communication. Itshould be noted that the method 1500 is just one implementation and thatthe operations of the method 1500 may be rearranged or otherwisemodified such that other implementations are possible.

FIG. 16 is a flow chart illustrating a method 1600 of wirelesscommunication, in accordance with various aspects of the presentdisclosure. For clarity, the method 1600 is described below withreference to aspects of one of the first eNBs 105 or the device 605configured as a first eNB, as described with reference to FIG. 1, 2, 3,4, 5, 6, 9, 10, or 12, aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,6, 7, 8, or 1, or aspects of one of the second eNBs 135 or the device605 configured as a second eNB, as described with reference to FIG. 1,2, 3, 4, 5, 6, or 12. In one implementation, the wireless communicationmanagement module 620 described with reference to FIG. 6, 9, 10, or 12may execute one or more sets of codes to control the functional elementsof a first eNB 105 or the device 605 configured as a first eNB toperform the functions described below.

At block 1605, a first eNB may coordinate, for a UE, multi-connectivitycommunication with at least the first eNB and a second eNB. In somecases, the first eNB may include a master eNB and the second eNB mayinclude a secondary eNB. The operation(s) at block 1605 may be performedor managed using the wireless communication management module 620described with reference to FIG. 6, 9, 10, or 12, or the UEmulti-connectivity management module 905 described with reference toFIG. 9 or 10.

At block 1610, an allocation of uplink transmit power between the firsteNB and at least the second eNB may be determined for the UE. Theallocation of uplink transmit power may in some cases include anallocation of maximum uplink transmit power, or a percentage of uplinktransmit power, to each of the first eNB and at least the second eNB.The operation(s) at block 1610 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 9, 10, or 12, or the uplink transmit power determination module910 described with reference to FIG. 9 or 10.

In some embodiments, the first eNB may determine an allocation of uplinktransmit power between a plurality of cells of the first eNB based onthe indication including the allocation of uplink transmit power betweenthe device first eNB and at least the second eNB. The allocation ofuplink transmit power between the plurality of cells may in some casesbe semi-statically specified in the indication (e.g., the first eNB mayspecify or configure an uplink transmit power value for each cell, whichuplink transmit power value may be used by the UE until the UE receives,from the first eNB, an adjusted indication including an allocation ofuplink transmit power between the first eNB and at least the secondeNB). The allocation of uplink transmit power between the plurality ofcells may in other cases be semi-statically specified per time index inthe indication (e.g., the first eNB may specify or configure multipleuplink transmit power values for each cell, for each time index, whichuplink transmit power values may be used by the UE until the UEreceives, from the first eNB, an adjusted indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB).

At block 1615, an indication including the allocation of uplink transmitpower allocation may be transmitted from the first eNB to the UE. Theoperation(s) at block 1615 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 9, 10, or 12, or the uplink transmit power communication module915 described with reference to FIG. 9 or 10.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including the allocation ofuplink transmit power between the first eNB and at least the second eNBmay be based at least in part on an UL/DL configuration of the first eNBor the second eNB. For example, when an eNB operates in a TDD mode, thenumber of active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

Therefore, the method 1600 may be used for wireless communication. Itshould be noted that the method 1600 is just one implementation and thatthe operations of the method 1600 may be rearranged or otherwisemodified such that other implementations are possible.

FIG. 17 is a flow chart illustrating a method 1700 of wirelesscommunication, in accordance with various aspects of the presentdisclosure. For clarity, the method 1700 is described below withreference to aspects of one of the first eNBs 105 or the device 605configured as a first eNB, as described with reference to FIG. 1, 2, 3,4, 5, 6, 9, 10, or 12, aspects of one of the UEs 115 or the device 605configured as a UE, as described with reference to FIG. 1, 2, 3, 4, 5,6, 7, 8, or 1, or aspects of one of the second eNBs 135 or the device605 configured as a second eNB, as described with reference to FIG. 1,2, 3, 4, 5, 6, or 12. In one implementation, the wireless communicationmanagement module 620 described with reference to FIG. 6, 9, 10, or 12may execute one or more sets of codes to control the functional elementsof a first eNB 105 or the device 605 configured as a first eNB toperform the functions described below.

At block 1705, a first eNB may coordinate, for a UE, multi-connectivitycommunication with at least the first eNB and a second eNB. In somecases, the first eNB may include a master eNB and the second eNB mayinclude a secondary eNB. The operation(s) at block 1705 may be performedor managed using the wireless communication management module 620described with reference to FIG. 6, 9, 10, or 12, or the UEmulti-connectivity management module 905 described with reference toFIG. 9 or 10.

At block 1710, an allocation of uplink transmit power between the firsteNB and at least the second eNB may be determined for the UE. Theallocation of uplink transmit power may in some cases include anallocation of maximum uplink transmit power, or a percentage of uplinktransmit power, to each of the first eNB and at least the second eNB.The operation(s) at block 1710 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 9, 10, or 12, or the uplink transmit power determination module910 described with reference to FIG. 9 or 10.

In some embodiments, the first eNB may determine an allocation of uplinktransmit power between a plurality of cells of the first eNB based onthe indication including the allocation of uplink transmit power betweenthe device first eNB and at least the second eNB. The allocation ofuplink transmit power between the plurality of cells may in some casesbe semi-statically specified in the indication (e.g., the first eNB mayspecify or configure an uplink transmit power value for each cell, whichuplink transmit power value may be used by the UE until the UE receives,from the first eNB, an adjusted indication including an allocation ofuplink transmit power between the first eNB and at least the secondeNB). The allocation of uplink transmit power between the plurality ofcells may in other cases be semi-statically specified per time index inthe indication (e.g., the first eNB may specify or configure multipleuplink transmit power values for each cell, for each time index, whichuplink transmit power values may be used by the UE until the UEreceives, from the first eNB, an adjusted indication including anallocation of uplink transmit power between the first eNB and at leastthe second eNB).

At block 1715, an indication including the allocation of uplink transmitpower allocation may be transmitted from the first eNB to the UE. Theoperation(s) at block 1715 may be performed or managed using thewireless communication management module 620 described with reference toFIG. 6, 9, 10, or 12, or the uplink transmit power communication module915 described with reference to FIG. 9 or 10.

In some embodiments, such as when the first eNB or the second eNBoperates in a TDD mode, the indication including the allocation ofuplink transmit power between the first eNB and at least the second eNBmay be based at least in part on an UL/DL configuration of the first eNBor the second eNB. For example, when an eNB operates in a TDD mode, thenumber of active uplink carriers can change over time based on the TDDconfiguration of each cell within the eNB. When the number of activeuplink carriers used by an eNB is less during a particular time period,more of the total uplink transmit power available to a UE during thetime period may be allocated to another eNB with which the UE maycommunicate during the time period. Conversely, more of the total uplinktransmit power available to the UE during the time period may beallocated to an eNB when the number of active uplink carriers used bythe eNB is greater during a particular time period.

In some embodiments, the indication including the allocation of uplinktransmit power between the first eNB and at least the second eNB mayinclude an indication of subframes on which substantially all transmitpower may be allocated to the first eNB or to the second eNB. Forexample, during a subframe or time period in which no uplinkcommunications to an eNB are expected, substantially all uplink transmitpower may be allocated to one or more other eNBs.

In some cases, the indication may include a time index. The time indexmay be used to indicate the subframes or time periods in which an eNB isallocated a particular uplink transmit power, and may be used toallocate different uplink transmit powers to different eNBs within asubframe or time period.

At block 1720, a power headroom report including power headroominformation for at least the first eNB and the second eNB may bereceived from the UE. In some cases, the power headroom report may bereceived in response to at least one of: an uplink transmit power of theUE for the second eNB, a measured pathloss variation for the second eNB,or the second eNB activating an uplink cell, as described with referenceto block 1420 of FIG. 14. In some cases, the power headroom report maybe received in response to the first eNB sending a triggering message(e.g., a request for a power headroom report) to the UE.

At block 1725, the power headroom report may be optionally transmittedfrom the first eNB to the second eNB.

In some embodiments, the power headroom report may indicate that the UEhas modified the allocation of uplink transmit power between the firsteNB and the second eNB, and at block 1730, the first eNB may determine,based on the power headroom report, that the UE has modified theallocation of uplink transmit power between the first eNB and the secondeNB. In other embodiments, the power headroom report may not indicatethat the UE has modified the allocation of uplink transmit power betweenthe first eNB and the second eNB.

At block 1735, the allocation of uplink transmit power between the firsteNB and the second eNB for the UE may be adjusted based on the powerheadroom report. In some cases, the adjustment may be based on amodification by the UE to the allocation of uplink transmit powerbetween the first eNB and the second eNB, as determined at block 1730.

At block 1740, the adjusted allocation of uplink transmit power may betransmitted to at least one of the UE or the second eNB.

In some embodiments of the method 1700, the adjustment of the allocationof uplink transmit power between the first eNB and the second eNB forthe UE, at block 1735, may also or alternately be made based on amessage received at the first eNB from the second eNB. The message mayinclude the power headroom report of the UE or information generated bythe second eNB.

In some embodiments of the method 1700, the first eNB may schedulecommunications (e.g., downlink or uplink communications) with the UE.The communications between the UE and the first eNB may be scheduledindependently from communications between the UE and the second eNB.

Therefore, the method 1700 may be used for wireless communication. Itshould be noted that the method 1700 is just one implementation and thatthe operations of the method 1700 may be rearranged or otherwisemodified such that other implementations are possible.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may, individually or collectively, be implementedor performed with one or more application-specific integrated circuits(ASICs) adapted to perform some or all of the applicable functions inhardware. Alternatively, the functions may be performed by one or moreother processing units (or cores) such as a general-purpose processor ora digital signal processor (DSP), or on one or more integrated circuits.A general-purpose processor may be a microprocessor, any conventionalprocessor, controller, microcontroller, state machine, or combinationthereof. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor,multiple microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration. In other embodiments,other types of integrated circuits may be used (e.g.,Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), andother Semi-Custom ICs), which may be programmed in any manner known inthe art. The functions of each of the blocks and modules may also beimplemented, in whole or in part, with instructions embodied in amemory, formatted to be executed by one or more general orapplication-specific processors.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. Also, as used herein, including in theclaims, “or” such as when used in a list of items prefaced by “at leastone of” indicates a disjunctive list such that, for example, a list of“at least one of A, B, or C” means A or B or C or AB or AC or BC or ABC(i.e., A and B and C).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, or digitalsubscriber line (DSL), then the coaxial cable, fiber optic cable,twisted pair, or DSL are included in the definition of medium. Disk anddisc, as used herein, include compact disc (CD), laser disc, opticaldisc, digital versatile disc (DVD), floppy disk and Blu-ray disc wheredisks usually reproduce data magnetically, while discs reproduce dataoptically with lasers. Combinations of the above are also includedwithin the scope of computer-readable media.

The detailed description set forth above in connection with the appendeddrawings is provided to enable a person skilled in the art to make oruse the disclosure. Various modifications to the disclosure will bereadily apparent to those skilled in the art, and the generic principlesdefined herein may be applied to other variations without departing fromthe spirit or scope of the disclosure. Throughout this disclosure theterm “example” or “exemplary” indicates an example or instance and doesnot imply or require any preference for the noted example. The detaileddescription includes specific details for the purpose of providing anunderstanding of the described techniques. These techniques, however,may be practiced without these specific details. In some instances,well-known structures and devices are shown in block diagram form inorder to avoid obscuring the concepts of the described embodiments.Thus, the disclosure is not to be limited to the examples and designsdescribed herein but is to be accorded the widest scope consistent withthe principles and novel features disclosed herein.

What is claimed is:
 1. A method of wireless communication by a user equipment (UE), comprising: establishing a connection with a first evolved NodeB (eNB) and a second eNB, wherein each of the first eNB and the second eNB provide radio resources to the UE for respective uplink communications; receiving from the first eNB, at the UE, an indication comprising an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmitting the uplink communications from the UE to the first eNB and the second eNB based on the indication.
 2. The method of claim 1, further comprising: generating a power headroom report at the UE comprising power headroom information for both the first eNB and the second eNB; and transmitting the power headroom report to the first eNB.
 3. The method of claim 2, wherein the power headroom information is based at least in part on scheduling information from both the first eNB and the second eNB; and wherein the first eNB and the second eNB schedule communications with the UE on different sets of resources.
 4. The method of claim 2, wherein the power headroom report is transmitted to the first eNB or the second eNB in response to a triggering message received from the first eNB or the second eNB.
 5. The method of claim 4, wherein the triggering message comprises an indication that the first eNB or the second eNB has activated an uplink cell.
 6. The method of claim 2, further comprising: transmitting the power headroom report to the second eNB.
 7. The method of claim 2, further comprising: triggering the power headroom report at the UE based on a measured pathloss of the second eNB.
 8. The method of claim 1, further comprising: modifying, by the UE, the allocation of uplink transmit power between the first eNB and the second eNB.
 9. The method of claim 8, wherein the modification of the allocation of uplink transmit power is based on a priority of uplink data or control information for one of the eNBs with respect to the other of the eNBs.
 10. The method of claim 1, further comprising: determining, at the UE, an uplink transmit power for each of a plurality of cells controlled by the first eNB or the second eNB based on the indication.
 11. The method of claim 1, wherein the first eNB comprises a master eNB and the second eNB comprises a secondary eNB.
 12. A device for wireless communication by a user equipment (UE), comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory, the instructions being executable by the processor to: establish a connection with a first evolved NodeB (eNB) and a second eNB, wherein each of the first eNB and the second eNB provide radio resources to the UE for respective uplink communications; receive from the first eNB, at the UE, an indication comprising an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmit the uplink communications from the UE to the first eNB and the second eNB based on the indication.
 13. The device of claim 12, wherein the instructions are executable by the processor to: generate a power headroom report at the UE comprising power headroom information for both the first eNB and the second eNB; and transmit the power headroom report to the first eNB.
 14. The device of claim 13, wherein the power headroom information is based at least in part on scheduling information from both the first eNB and the second eNB; and wherein the first eNB and the second eNB schedule communications with the UE on different sets of resources.
 15. The device of claim 13, wherein the power headroom report is transmitted to the first eNB or the second eNB in response to a triggering message received from the first eNB or the second eNB.
 16. The device of claim 15, wherein the triggering message comprises an indication that the first eNB or the second eNB has activated an uplink cell.
 17. The device of claim 13, wherein the instructions are executable by the processor to: transmit the power headroom report to the second eNB.
 18. The device of claim 13, wherein the instructions are executable by the processor to: trigger the power headroom report at the UE based on a measured pathloss of the second eNB.
 19. The device of claim 12, wherein the instructions are executable by the processor to: modify, by the UE, the allocation of uplink transmit power between the first eNB and the second eNB.
 20. The device of claim 19, wherein the modification of the allocation of uplink transmit power is based on a priority of uplink data or control information for one of the eNBs with respect to the other of the eNBs.
 21. The device of claim 12, wherein the instructions are executable by the processor to: determine, at the UE, an uplink transmit power for each of a plurality of cells controlled by the first eNB or the second eNB based on the indication.
 22. The device of claim 12, wherein the first eNB comprises a master eNB and the second eNB comprises a secondary eNB.
 23. A method of wireless communication, comprising: coordinating, by a first evolved NodeB (eNB), multi-connectivity communication for a user equipment (UE) with at least the first eNB and a second eNB; determining for the UE, at the eNB, an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmitting an indication comprising the allocation of uplink transmit power allocation from the first eNB to the UE.
 24. The method of claim 23, further comprising: adjusting the allocation of uplink transmit power between the first eNB and the second eNB based on a message received at the first eNB from the second eNB.
 25. The method of claim 23, further comprising: transmitting the allocation of uplink transmit power from the first eNB to the second eNB.
 26. The method of claim 25, wherein transmitting the allocation of uplink transmit power from the first eNB to the second eNB comprises: transmitting a message comprising the allocation of uplink transmit power over an X2 interface between the first eNB and the second eNB.
 27. A device for wireless communication, comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory, the instructions being executable by the processor to: coordinate, by a first evolved NodeB (eNB), multi-connectivity communication for a user equipment (UE) with at least the first eNB and a second eNB; determine for the UE, at the eNB, an allocation of uplink transmit power between the first eNB and at least the second eNB; and transmit an indication comprising the allocation of uplink transmit power allocation from the first eNB to the UE.
 28. The device of claim 27, wherein the instructions are executable by the processor to: adjust the allocation of uplink transmit power between the first eNB and the second eNB based on a message received at the first eNB from the second eNB.
 29. The device of claim 27, wherein the instructions are executable by the processor to: transmit the allocation of uplink transmit power from the first eNB to the second eNB.
 30. The device of claim 29, wherein the instructions executable by the processor to transmit the allocation of uplink transmit power from the first eNB to the second eNB comprises instructions executable by the processor to: transmit a message comprising the allocation of uplink transmit power over an X2 interface between the first eNB and the second eNB. 